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Comparative and Cost-Effectiveness Analyses of Resident Quality Outcomes in Nursing Homes Mayuko Uchida Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy under the Executive Committee of the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2014

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Page 1: Mayuko Uchida - Columbia University

Comparative and Cost-Effectiveness Analyses of

Resident Quality Outcomes in Nursing Homes

Mayuko Uchida

Submitted in partial fulfillment of the

requirements for the degree of

Doctor of Philosophy

under the Executive Committee

of the Graduate School of Arts and Sciences

COLUMBIA UNIVERSITY

2014

Page 2: Mayuko Uchida - Columbia University

©2014

Mayuko Uchida

All rights reserved

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ABSTRACT

Comparative and Cost-Effectiveness Analyses of Resident Quality Outcomes in Nursing Homes

Mayuko Uchida

Concerns about the quality of care in nursing homes (NHs) have continued to stimulate

research and debate over the past several decades. Although substantial improvements in NH

care have taken place, serious challenges remain. With enactment of the Patient Protection and

Affordable Care Act (PPACA) and recent NH Value Based Purchasing Demonstrations through

the Centers for Medicare and Medicaid Services (CMS), there has been increasing policy interest

to efficiently reduce potentially avoidable resident adverse outcomes and costs. Organized into

three separate studies, this dissertation explores the comparative and cost-effectiveness of

improving NH quality outcomes. The significance and current challenges surrounding NH care

quality is discussed in the First Chapter. To gain understanding of current infection prevention

interventions conducted in NHs, a systematic literature review was conducted and is presented in

Chapter Two. The Third Chapter reports on quantitative findings of NH infections as a function

of resident quality and tested variations in nurse workforce characteristics. The Fourth Chapter

reports on an economic analysis evaluating the implications of retaining a skilled nursing

workforce in NHs. Finally, the Fifth Chapter synthesizes the findings from the previous chapters

and serves as the concluding chapter of the dissertation.

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Table of Contents

Chapter 1: Introduction ............................................................................................................... 1

Resident Safety, Quality of Care and Costs in Nursing Homes .................................................. 2

Quality Indicators in Nursing Homes.......................................................................................... 3

Donabedian’s Framework of Healthcare Quality ........................................................................ 5

Infections in Nursing Homes....................................................................................................... 6

Pneumonia ............................................................................................................................... 7

Urinary Tract Infection ............................................................................................................ 7

Skin and Soft Tissue Infections-Pressure Ulcers ..................................................................... 8

Nurse Staffing and Resident Outcomes ...................................................................................... 8

Challenges—Infections, Hospitalizations, and Nurse Staffing ............................................... 8

Economic Evidence of Nurse Staffing on Resident Outcomes ............................................. 10

Significance and Gaps ............................................................................................................... 11

Aims and Hypotheses ................................................................................................................ 12

Potential Contributions .............................................................................................................. 13

Chapter 2: Systematic Review ................................................................................................... 15

Abstract ..................................................................................................................................... 16

Introduction ............................................................................................................................... 17

Methods ..................................................................................................................................... 18

Search Strategy ...................................................................................................................... 19

Selection Criteria ................................................................................................................... 19

Type of Studies ...................................................................................................................... 19

Outcome Measures ................................................................................................................ 20

Data Extraction ...................................................................................................................... 21

Assessment of Methodological Quality ................................................................................. 21

Results ....................................................................................................................................... 22

Study Selection ...................................................................................................................... 22

Characteristics of Studies ...................................................................................................... 22

Participants ............................................................................................................................ 24

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Outcomes ............................................................................................................................... 24

Methodological Quality of Studies ........................................................................................ 25

Discussion ................................................................................................................................. 26

Limitations ............................................................................................................................. 27

Implications for Practice and Future Research ...................................................................... 28

Conclusion ................................................................................................................................. 29

Chapter 3: Quantitative Analysis .............................................................................................. 39

Abstract ..................................................................................................................................... 40

Introduction ............................................................................................................................... 41

Background ............................................................................................................................ 42

Conceptual Framework .......................................................................................................... 43

Objective ................................................................................................................................ 44

Methods ..................................................................................................................................... 44

Data Sources .......................................................................................................................... 45

Data Preparation .................................................................................................................... 46

Operationalization of Variables ............................................................................................. 47

Outcome Variables ................................................................................................................ 47

Independent variables ............................................................................................................ 48

Process Variables ................................................................................................................... 49

Covariates .............................................................................................................................. 49

Data Analysis ............................................................................................................................ 50

Main Analysis Methods ......................................................................................................... 50

Robustness Checks ................................................................................................................ 51

Results ....................................................................................................................................... 52

Descriptive Statistics ............................................................................................................. 52

Composite Measure of Resident Infection Outcomes ........................................................... 52

Robustness Checks ................................................................................................................ 53

Discussion ................................................................................................................................. 54

Implications for Policy and Practice ...................................................................................... 55

Strengths and Limitations ...................................................................................................... 56

Conclusion ................................................................................................................................. 57

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Chapter 4: Economic Analysis ................................................................................................... 62

Abstract ..................................................................................................................................... 63

Introduction ............................................................................................................................... 64

Background ............................................................................................................................ 64

Objective ................................................................................................................................ 67

Methods ..................................................................................................................................... 67

Study Design/Time Horizon .................................................................................................. 68

Perspective: ............................................................................................................................ 70

Variables and Data Sources ................................................................................................... 70

Strategy-High versus Low RN Tenure .................................................................................. 71

Data Analysis-Base Case Analysis ........................................................................................... 72

Assumptions of Transitional Flow and Cost Calculations .................................................... 72

Sensitivity Analysis ................................................................................................................... 73

Results ....................................................................................................................................... 74

Discussion ................................................................................................................................. 75

Limitations ............................................................................................................................. 76

Conclusion ................................................................................................................................. 78

Chapter 5: Conclusion ................................................................................................................ 86

Summary of Systematic Review ............................................................................................... 87

Summary of Quantitative Findings ........................................................................................... 88

Quantitative Findings Informing the Economic Evaluation ..................................................... 89

Summary of Economic Evaluation ........................................................................................... 90

Strengths and Limitations.......................................................................................................... 91

Strengths ................................................................................................................................ 91

Limitations ............................................................................................................................. 92

Future Directions for Research ................................................................................................. 94

Summary of Practice Recommendations .................................................................................. 95

Summary of Policy Recommendations ..................................................................................... 96

Conclusion ................................................................................................................................. 96

References .................................................................................................................................... 98

List of Appendices ..................................................................................................................... 118

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Appendix A. MDS 2.0 Resident Assessment Form ................................................................ 119

Appendix B. PRISMA Checklist ............................................................................................ 128

Appendix C. Downs and Black (1998) Quality Assessment Tool .......................................... 133

Appendix D. Detailed Summary of Monthly Unit Level Nurse Workforce Characteristics .. 136

Appendix E. Correlation Matrix of Independent Variables .................................................... 137

Appendix F. Effects of Staffing on Composite under Different Model Assumptions ........... 138

Technical Appendix 1: Regression Model Justification ......................................................... 139

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List of Tables and Figures

Chapter 2: Systematic Review….………………………………………………………….…..15

Table 2.1: Select Study Characteristics and Quality of Included Studies ..................................... 31

Figure 2.1: Flow Diagram ............................................................................................................. 31

Chapter 3: Quantitative Analysis….…………………………………………………………..39

Figure 3.1: Adapted Model of Healthcare Quality ....................................................................... 58

Table 3.1: Characteristics of VA Community Living Centers ...... Error! Bookmark not defined.

Table 3.2: Effects of Staffing on Infection Composite (urinary tract infection, pneumonia,

pressure ulcer) ............................................................................................................................... 60

Table 3.3: Robustness Checks on Infection Composite................................................................ 61

Chapter 4: Economic Analysis…….…………………………………………………………..62

Table 4.1: CHEERS Statement ..................................................................................................... 79

Figure 4.1: Decision tree ............................................................................................................... 81

Table 4.2: Model Baseline Estimates............................................................................................ 82

Table 4.3: List of Major Assumptions .......................................................................................... 83

Table 4.4: Summary of 3 Base Case Models ................................................................................ 84

Table 4.5: Sensitivity Analyses..................................................................................................... 85

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Acknowledgements

First, I would like to express my deepest gratitude to my advisor, Dr. Patricia W. Stone,

for her mentorship, patience and continuous hours of support throughout my doctoral training at

Columbia University School of Nursing. Dr. Stone has been instrumental in my growth and

development as a beginning nurse researcher. I chose to come to Columbia because of Dr. Stone

and never will I regret this choice. Her encouragement and guidance has pushed me to go beyond

what I thought I could ever achieve. I would also like to thank my interdisciplinary research

team, Drs. Ciaran Phibbs and Susan Schmitt, who have provided ongoing support, expertise and

mentorship throughout this entire process. Furthermore, I would like to thank Dr. Haomiao Jia

for his thoughtful guidance, and always having an open door. I would also like to thank Drs. Jing

Jing Shang and Claire Wang for serving as members of my dissertation committee and guiding

me through the analytical processes. I am also deeply grateful to Dr. Elaine Larson for her

extraordinary co-mentorship and opening many doors for me during my doctoral studies.

I have been very fortunate to have been a PhD student at the School of Nursing. I would

like to thank my fellow classmates, the faculty, the amazing staff, especially Barbara Luna and

Kristine Kulage. I would like to thank my fellow doctoral students for keeping me sane and

balanced during the past few years. I especially want to thank Laurie Conway and Eileen Carter

for keeping me on track and encouraging me to keep going when I thought I could not finish. I

thank Pamela de Cordova, who has provided support, guidance and pearls of wisdom from Day 1

of my doctoral studies and for being a great friend. I also thank Monika Pogorzelska-Maziarz,

Carolyn Herzig and Katie Cohen for their unconditional support and always being phenomenal

colleagues.

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Most importantly, I would like to thank my parents and family for always believing in

me. None of this would have been possible without your love and support. Finally, I dedicate this

dissertation to my grandparents who will forever remain my inspiration for long-term care

nursing research.

Acknowledgement for Funding: This dissertation was supported by grant numbers

F31NR0138-01, T32NR07969-09S1, T90NR010824 from the National Institutes of Health,

National Institute of Nursing Research. Funding was also generously provided by Jonas Center

for Nursing Excellence.

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Chapter 1: Introduction

This introductory chapter presents an overview of nursing home (NH) quality of care and

importance of resident safety. Quality and safety are described in the context of potentially

avoidable NH infections, NH resident hospitalizations, and its economic implications. Previous

literature illuminating the relationship between NH nurse workforce and resident outcomes are

discussed. Gaps in knowledge are identified and the chapter concludes with the aims of the

dissertation and potential contributions of this work to inform future NH practice and policy.

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Resident Safety, Quality of Care and Costs in Nursing Homes

Concerns about the quality of care in nursing homes (NHs) have persisted over the past

several decades among policymakers and the public. In 1986, the Institute of Medicine (IOM)

(IOM, 1986) published the landmark report, Improving the Quality of Care in Nursing Homes;

while this report documented serious quality of care problems, it helped establish specific steps

necessary to protect NH residents’ right to safety. It further served as the basis for the Nursing

Home Reform Act, which was embedded in the Congressional Legislation Omnibus Budget

Reconciliation Act of 1987 (OBRA-87). This act mandated extensive NH regulatory controls;

however, regulations alone have failed to eliminate the ongoing quality of care problems

(Werner & Konetzka, 2010). In 1999, the release of another IOM Report (IOM, 1999), To Err is

Human: Building a Safer Health System, highlighted the importance of resident safety and the

occurrence of adverse events as a quality issue. It also contributed to acknowledging the role of a

safety culture within institutions by de-emphasizing individual blame and fostering shared

accountability (Gruneir & Mor, 2008). As a result, promoting resident safety has become

interconnected with providing quality care and remains an essential focus for many NH

providers and policymakers.

Another important focus is improving resident safety and quality while reducing costs. In

2011, national healthcare spending reached $2.7 trillion, or $8,680 per person and the elderly

consumed the vast majority of these costs (CMS, 2013a). Of the 1.5 million people living in the

nation’s NHs, many are older than 65 years, with mean age of 85 years old (Jones, Dwyer,

Bercovitz & Strahan, 2009). Public spending on NH care accounts for more than 6% of total

Medicare expenditures (i.e., more than $20 billion annually) and is expected to increase (AHCA,

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2011; CMS, 2011a);occurrence of avoidable adverse events such as infections and unnecessary

hospitalizations can result in additional healthcare expenditures (Grabowski, O'Malley, &

Barhydt, 2007). Recently, as part of the Patient Protection and Affordable Care Act (PPACA),

policy interventions such as the NH Value Based Purchasing Demonstrations (i.e., pay-for-

performance) have emerged to shift emphasis toward providing quality rather than the quantity

of care (Werner & Konetzka, 2010). Efforts for improving care are now linking healthcare

spending to quality and efficiency by rewarding high performing NHs (i.e., additional payments)

for improving resident outcomes (CMS, 2011b).

Quality Indicators in Nursing Homes

OBRA-87 has greatly changed the way NHs operate today. Some of the major

components of OBRA-87 included revised NH care standards, a more stringent survey process

for NHs to receive federal certification (i.e., to be inspected at least once every 15 months), and

use of the Resident Assessment Instrument to monitor and assess quality (IOM, 2001). To

quantify “quality” in NHs, numerous indicators have been developed. While currently available

indicators have been criticized for not directly measuring quality per se, they are still widely used

as surrogate measures of care excellence (Castle & Ferguson, 2010).The Resident Assessment

Instrument, perhaps the most prominent component of OBRA-87 is facilitated by the Minimum

Data Set (MDS) (Appendix A) and is the source for many quality indicators developed today.

Implemented nationally in 1991, the MDS is a government mandated dataset containing

information on functional status and health conditions for all residents in Medicare or Medicaid

certified facilities (Castle & Ferguson, 2010; Gruneir & Mor, 2008). MDS assessments are

conducted by NHs at regular intervals (i.e., at least once per quarter) and the data are used to

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determine each resident’s needs and to develop an individual plan of care. With information

from the MDS, many quality indicators have been developed around resident outcomes such as

falls, urinary tract infections, and bladder/bowel incontinence. However, the issue with

ascertainment bias has been of concern with using MDS measures in research (Sangl, Saliba,

Gifford, & Hittle, 2005). In particular, despite rigorous psychometric development and testing,

the reliability and validity of the data have been subject to criticism (Rahman & Applebaum,

2009). The retrospective nature of the MDS assessments and inter-rater variability are often

raised as problems influencing the usefulness of the data (Castle & Ferguson, 2010).

Even though the MDS was not developed specifically for research purposes, it is the only

comprehensive standardized assessment tool that tracks changes in care at the resident level (Del

Rio, Goldman, Kapella, Sulit, & Murray, 2006; Rantz & Connolly, 2004). To date, many

research studies conducted in NHs have utilized MDS records to examine quality of care (Castle

& Engberg, 2007; French et al., 2007; Konetzka, Stearns, & Park, 2008).

Another commonly used measure of NH quality is deficiency citations (Castle, Wagner,

Ferguson, & Handler, 2011; Castle, Wagner, Ferguson-Rome, Men, & Handler, 2011).

Deficiency citations are given when NHs fail to meet federal certification requirements. There

are approximately 180 possible deficiencies and violations, which are assessed on scope and

severity of harm to residents. Violations are graded on a scale of “A” (isolated and no harm= 0

points) to “L” (immediate jeopardy and widespread harm pattern= 150 points). Deficiency

citations categorized as “F” (potential for widespread harm) and higher are considered

substandard quality of care. Detection bias has been raised as a measurement issue inherent to

deficiency citations. A high degree of variation in the use of deficiency citations have been

reported across states (Castle & Ferguson, 2010). Nevertheless, deficiency citations are one way

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NHs are being inspected on whether or not they meet current federal safety and quality

standards.

Quality indicators created from the national MDS repository and deficiency citations

have been pulled together in the form of a report card known as Nursing Home Compare

(http://www.medicare.gov/nursinghomecompare/search.html). Since its release in 2002, Nursing

Home Compare has provided facility level information on over 16,000 federally certified NHs

across the nation (CMS, 2013b). It allows consumers to compare information about NHs in areas

of health inspections, staffing and quality measures (e.g., percentage of residents with urinary

tract infections, falls, pressure ulcers). Such public reporting movements have been reported to

potentially influence quality of care; early evaluations of Nursing Home Compare have reported

improvements in many targeted quality measures (Mukamel, Weimer, Spector, Ladd, & Zinn,

2008).

Donabedian’s Framework of Healthcare Quality

One approach of conceptualizing quality in NHs is using a framework proposed by

Donabedian (1966). According to Donabedian, quality healthcare is defined along three basic

dimensions: structures, processes, and outcomes. In his seminal work, Donabedian defines the

structures of care as administrative and related processes that support and direct the provision of

care, including the regulatory environment and human resources (e.g., nurse staffing). The

processes of care are the actions or services involved with direct provision of care. The outcomes

of care are the consequences or results that can be attributed to the processes. The theoretical

underpinnings of this framework are that good structures should facilitate good processes and

good processes should facilitate good outcomes (Castle & Ferguson, 2010; Gruneir & Mor,

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2008). In addition, good structures may also directly impact outcomes. While this framework

has established a fairly robust model for studying the clinical care domains of quality in NHs

(Castle & Ferguson, 2010), the extent to which these structural and process characteristics

impact resident adverse outcomes, particularly around infections in NHs is limited. This

theoretical framework guided the development of this dissertation.

Infections in Nursing Homes

For NH residents, infections are a leading cause of morbidity and mortality despite often

being preventable (Richards, 2007). It is estimated that 1.6 to 3.8 million infections occur each

year in NHs and lead to approximately 388,000 deaths (Strausbaugh & Joseph, 2000). Infections

are also the most common reasons for hospitalizations, accounting for 27 to 63 percent of all

resident transfers (Boockvar et al., 2005; Richards, 2002; Strausbaugh & Joseph, 2000). Cost

estimates for infections in NHs range from $673 million to $2 billion annually (Strausbaugh &

Joseph, 2000; Teresi, Holmes, Bloom, Monaco, & Rosen, 1991). Furthermore, NH residents are

at high risk for infections caused by multiple drug resistant organisms (MDROs) (Smith et al.,

2008), which adds to the complexity of prevention and management as well as costs.

Recently, increased attention has been focused on reducing infections in NHs. The

original publication of the 2009 National Action Plan to Reduce Infections primarily focused on

the acute care setting (U.S. Department of Health and Human Services, 2009); in April 2013, the

U.S. Department of Health and Human Services released a third phase of the report specifically

addressing infections in long term care (U.S. Department of Health and Human Services, 2013).

Given the high prevalence of NH residents with functional decline, dementia, incontinence, poor

oral hygiene and swallowing difficulties, some common infections highlighted were pneumonia,

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urinary tract infections (UTIs), and skin and soft tissue infections (Smith et al., 2008; U.S.

Department of Health and Human Services, 2013).

Pneumonia

For residents over the age of 65, pneumonia remains a leading cause of morbidity and

mortality, resulting in almost half of all infectious disease related hospitalizations and deaths

(Smith et al., 2008; Spector, Mutter, Owens & Limcangco, 2012). Compared to community-

dwelling older adults, NH residents were more than 10 times likely to be treated and hospitalized

for pneumonia in a given year (Dosa, 2005). Hospitalization for pneumonia increases with age.

Among the 75-84 year olds and those over 85 years account for 19.7 and 35.9 stays per 1000

population, respectively. These rates were two and four times higher than for patients 65-74

years old (Fry, Shay, Holman, Curns, & Anderson, 2005; Wier, 2010). While there is growing

evidence to suggest that hospitalization of residents with pneumonia is not required and may

actually result in increased cost, morbidity and mortality (Dosa, 2005), atypical presentation of

pneumonia symptoms in the elderly makes early diagnosis and management extremely difficult

(Smith et al., 2008).

Urinary Tract Infection

Even though UTIs do not result in as much mortality as pneumonia, nevertheless it is

another commonly diagnosed and treated infection in NHs (Ouslander, Diaz, Hain, & Tappen,

2011). Additionally, it is the most common diagnosis indicated for antibiotic prescription usage

in NHs and has been cited to be the most costly and resource intensive condition among

Medicare beneficiaries (Tena-Nelson et al., 2012; U.S. Department of Health and Human

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Services, 2013). UTIs are also one of the main drivers of hospitalizations and account for almost

30% of hospital readmissions from NHs within 30 days (Ouslander et al., 2011).

Skin and Soft Tissue Infections-Pressure Ulcers

Skin and soft tissue infections are another common type of infection among the NH

population (Horn, Buerhaus, Bergstrom, & Smout, 2005). With aging, the skin barrier becomes

thinner and protective subcutaneous tissues decline which put residents at high risk for pressure

ulcer formation and subsequent bacterial infection (Smith et al., 2008). While a pressure ulcer by

itself is not considered to be infectious, infections occur in up to 65% of pressure ulcers and may

subsequently lead to more serious, costly complications such as osteomyelitis and sepsis (U.S.

Department of Health and Human Services, 2013). Furthermore, having a pressure ulcer has

been found to expedite a resident’s time for hospitalization (O'Malley, Caudry, & Grabowski,

2011).

Nurse Staffing and Resident Outcomes

While physicians take part in managing some of the services, the majority of care in NHs

is provided by nursing personnel. Relative to acute care settings, which have a higher proportion

of registered nurses (RNs), NHs employ more licensed practical nurses (LPNs), and nursing

assistants (NAs) (Harrington, 2005a). Nursing personnel are at the frontline of reducing resident

adverse outcomes in NHs. Understanding how this workforce provides safe, high quality, cost-

efficient care is a national priority.

Challenges—Infections, Hospitalizations, and Nurse Staffing

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Over the past several years, a considerable amount of research has been devoted to

examining the number and composition of nurse staffing in NHs (Bostick, Rantz, Flesner, &

Riggs, 2006; Castle & Engberg, 2007; Hyer et al., 2011; Kim, Kovner, Harrington, Greene, &

Mezey, 2009; Konetzka, 2008; Schnelle et al., 2004). In general, higher staffing levels have been

associated with reduced mortality, fewer resident and facility level deficiencies, fewer

catheterized residents, and better pain management (Castle & Anderson, 2011; Collier &

Harrington, 2008).

Potentially preventable infections and hospitalizations in NHs have also been reported as

indicators of poor quality care (Ouslander et al., 2011). Recently, it was reported that 15 percent

of the nation’s NHs received annual deficiency citations for infection control, and low nurse

staffing levels were positively associated with these citations (Castle, Wagner, Ferguson-Rome,

et al., 2011). The relationship between greater RN staffing and lower resident hospitalizations is

known; facilities with higher ratios of RNs to total nursing staff had lower risks for avoidable

hospitalizations compared to residents in NHs with lower ratios (Intrator, Zinn, & Mor, 2004).

While associations between increased nurse staffing levels and decreased resident

adverse outcomes have been found in other NH studies, the majority of this work has been cross-

sectional or limited by examining nurse staffing only at the facility levels (e.g., not specific to a

NH unit) (Kim, Harrington, & Greene, 2009; Konetzka et al., 2008). A review by Castle (Castle,

2008) analyzing the staffing-quality relationship in NHs illuminated these methodological flaws.

Of the 59 empirical studies analyzed, only 8 studies employed a longitudinal design and 50

studies used data from a large administrative database collected from self-reported surveys at the

facility level.

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While much of the literature has tended to focus on nurse staffing levels (i.e., total

nursing hours per resident day), other characteristics of the workforce such as experience and

percentage of hours worked by various nurse types such as NAs and agency nurses are also

important and may influence resident outcomes (Bartel, 2011; Castle, 2009; Castle & Anderson,

2011; Weech-Maldonado, Meret-Hanke, Neff, & Mor, 2004). One emerging area of focus is the

persistently high rate of nurse turnover in NHs (Castle, Engberg, & Men, 2007). Relative to

acute care settings, NHs experience higher staffing shortages; annual turnover rates have been

reported to average 49% for RNs and 71% for NAs (AHCA, 2005; AHCA, 2012). Despite the

large body of studies examining antecedents of turnover in NHs, only few have examined the

impact of turnover on quality (Castle, 2005; Castle et al., 2007; Spector & Takada, 1991; K. S.

Thomas, Mor, Tyler, & Hyer, 2013; Zimmerman, Gruber-Baldini, Hebel, Sloane, & Magaziner,

2002). With recent enactment of the PPACA, examining nurse turnover, retention and avoidable

hospitalizations in NHs have become a major focus as they may soon become publicly reported

quality indicators (CMS, 2011b).

Economic Evidence of Nurse Staffing on Resident Outcomes

As healthcare costs increase, efforts to improve the healthcare system efficiently and

effectively must consider the value the nurse workforce brings to the quality of care in NHs

(Horn, 2008). Previous researchers examining the nurse staffing-outcomes relationships in NHs

primarily examined workforce attributes and resident outcomes without considering the costs of

care (Harrington, 2005b). Of the few studies which examined nurse staffing levels and costs

(Dorr, Horn, & Smout, 2005; Ganz, Simmons, & Schnelle, 2005), only a small number of studies

have explored the economic consequences related to high nurse turnover and low retention

(Caudill & Patrick, 1991; Jones & Gates, 2007). Conducting cost-effectiveness analysis (CEA)

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has been identified as a potential way to examine tradeoffs between cost and quality (Harrington,

2005b; Siegel & Clancy, 2006).

Significance and Gaps

Substantial improvements in the quality of NH care have taken place, however, many

challenges remain. First, while there are published guidelines for infection prevention and

control in NHs, our knowledge of effective prevention and control measures remain largely

inadequate. Most infection prevention interventions in NHs have predominantly been adapted

from those designed for acute care. Compared to hospitals, NHs often provide care for chronic

functionally impaired residents for a prolonged period of time with fewer available resources

(Castle & Engberg, 2007; Mody et al., 2011). If NH staff are to make use of effective

interventions in their clinical practice, there is need to better understand the current state of the

science surrounding infection prevention interventions conducted in NHs.

Second, while associations between nurse workforce characteristics and infections are

well documented in hospitals, the evidence base examining these relationships in NH settings has

not been as extensive. Furthermore, due to lack of access to unit-specific data, several past

studies that examined nurse workforce characteristics used the facility as the unit of observation

(Castle, 2008). For example, using facility level administrative datasets only allows resident and

nurse staffing data to be traced to the facility. Using facility-level measurement of staffing can be

a disadvantage especially when attempting to link staffing to the resident point of care. To

overcome weaknesses encountered in previous studies, there is need to conduct analyses at the

unit-level. No studies have simultaneously examined the longitudinal impact of various nurse

workforce characteristics (e.g., role of tenure and percentage of hours worked by different nurse

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types) on resident infection outcomes using a dataset that standardizes data collection across all

NH units.

Finally, despite the public policy importance, economic studies evaluating the impact of

the NH nurse workforce on resident outcomes is limited (Dorr et al., 2005; Ganz et al., 2005;

Horn, 2008). Particularly lacking is the financial implications from retaining a skilled nurse

workforce in NHs. Nurse retention and turnover are important, complementary components of

quality (Jones, 2004), yet studies quantifying the consequences of nurse retention on resident

hospitalizations does not exist. Unless NH administrators can better quantify the financial impact

of reducing turnover and retaining a skilled nursing workforce, they may be unwilling to make

additional resource investments.

There are many gaps in knowledge about how best to evaluate cost-efficient care to

reduce adverse outcomes in NHs. This dissertation will help fill these gaps in the literature.

Aims and Hypotheses

Aim 1: To critically review and synthesize current evidence and the methodological quality

of infection prevention interventions in NHs.

To address this aim, a systematic review was undertaken and examined infection

prevention interventions conducted in NHs from 2001 to 2011. Methods and findings for this

aim are presented in Chapter 2.

Aim 2: To estimate the effects of various nurse workforce characteristics on changes in

resident infection related outcomes in NHs.

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To address Aim 2, a secondary analysis of a six-year longitudinal dataset was conducted.

Data came from a national sample of Department of Veterans Affairs (VA) Community Living

Centers (CLCs), formerly known as VA NHs. Findings from this Aim are presented in Chapter

3. This aim has 3 hypotheses:

Hypothesis 2.1: Controlling for resident and unit characteristics, as nurse staffing hours

of care increase, the risk of resident infection outcomes will decrease.

Hypothesis 2.2: Controlling for resident and unit characteristics, as the percentage of

hours worked by RNs increase, the risk of resident infection outcomes will decrease.

Hypothesis 2.3: Controlling for resident and unit characteristics, as nurse tenure on a unit

increase, the risk of resident infection outcomes will decrease.

Aim 3: To evaluate the cost-effectiveness of two nurse workforce scenarios focusing on RN

tenure (high versus low), the associated conditional probabilities of transfers from NH to

the hospital and the resulting costs.

Aim 3 was informed by findings from Aim 2, which highlighted the importance of

retaining a skilled workforce to reduce adverse events. A simple cost-effectiveness analysis

using a decision tree model was conducted. Details are presented in Chapter 4.

Potential Contributions

With the limited resources available, NH administrators and policymakers need to know

the evidence base behind quality and costs before implementing any major structural changes.

Therefore, an anticipated contribution of this dissertation work is to provide a comprehensive

understanding of current challenges around resident adverse outcomes and to evaluate the

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potential contribution of the NH nurse workforce for improving resident safety, quality of care,

and reducing healthcare costs. Results from each of the aims have been developed as stand-alone

manuscripts that are either published (Aim 1), submitted for publication (Aim 2), or in

preparation for submission (Aim 3).

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Chapter 2: Systematic Review

This chapter is a systematic review of the literature examining infection prevention

interventions in NHs. The review was conducted to critically review and synthesize current

evidence and the methodological quality of non-pharmacologic infection prevention

interventions for older adults residing in NHs. The review was guided by the Preferred Reporting

Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. This paper was

submitted and published in the Journal of the American Geriatrics Society (Uchida, Pogorzelska-

Maziarz, Smith & Larson, 2013).

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Abstract

The purpose of this systematic review is to critically review and synthesize current

evidence and the methodological quality of non-pharmacologic infection prevention

interventions in long-term care (LTC) facilities for older adults. Two reviewers searched 3

electronic databases for studies published over the last decade assessing randomized and non-

randomized trials designed to reduce infections in older adults in which primary outcomes were

infection rates and/or reductions of risk factors related to infections. To establish clarity and

standardized reporting of findings, the PRISMA checklist was used. Data extracted included

study design, sample size, type and duration of interventions, outcome measures reported, and

findings. Study quality was independently assessed by two reviewers using a validated quality

assessment tool. Twenty-four articles met inclusion criteria; the majority was randomized control

trials (67%), where the primary purpose was to reduce pneumonia (66%). Thirteen (54%) studies

reported statistically significant results in favor of interventions on at least one of their outcome

measures. The methodological clarity of available evidence was limited, placing them at

potential risk of bias. Gaps and inconsistencies surrounding interventions in LTC are evident.

Future interventional studies need to enhance methodological rigor using clearly defined

outcome measures and standardized reporting of findings.

Keywords: infections, nursing homes, interventions

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Introduction

Infections in residents of long-term care (LTC) facilities are common, costly, and

associated with significant morbidity and mortality (Jones, Dwyer, Bercovitz & Strahan, 2009).

Institutionalized adults over the age of 65 years account for a disproportionate number of

infections in LTC settings (Richards, 2002). An estimated 1.6 to 3.8 million infections occur

each year in LTC facilities across the nation and lead to approximately 388,000 deaths

(Strausbaugh & Joseph, 2000). Additionally, infections in LTC result in frequent

hospitalizations, accounting for 27 to 63 percent of all resident transfers ( Richards, 2002;

Strausbaugh & Joseph, 2000). Cost estimates for infections in LTC range from $673 million to

$2 billion annually (Strausbaugh & Joseph, 2000). Despite such high mortality and costs

associated with infections, a proportion may be preventable (Smith et al., 2008; Strausbaugh &

Joseph, 2000).

Elder LTC residents are especially vulnerable to a variety of infections due to immune

dysfunction associated with aging, functional and cognitive limitations and the presence of

multiple co-morbidities that affect the integrity of host resistance ("Older Americans 2010 Key

Indicators of Well-Being," 2010). Common endemic infections in LTC include urinary tract

infections (UTIs) and respiratory tract infections (Smith et al., 2008). Outbreaks are also

frequently reported and the most common are respiratory and enteric conditions (Jones et al.,

2009; Smith et al., 2008). Older adults in these settings also undergo frequent care transitions

which have implications for the spread of pathogens (Mody et al., 2011; Rogers, 2008).

Colonization with multiple drug resistant organisms (MDROs) such as methicillin-resistant

Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) in both endemic

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and epidemic infections is increasingly prevalent (Smith et al., 2008) which adds to the

complexity of prevention and management in this older population.

While there are published guidelines for infection prevention and control in LTC,

effective prevention and control measures remain largely inadequate (Smith et al., 2008). Most

infection prevention interventions in LTC have predominantly been adapted from those designed

for acute care—a clinical setting much different from LTC. Compared to hospitals, LTC

facilities often provide care for chronic functionally impaired residents for a prolonged period of

time with fewer available resources (Castle & Engberg, 2007; Mody et al., 2011). Therefore,

directly applying hospital-based interventions to LTC is often unrealistic and may be inefficient

given the nature of LTC settings. Identifying evidence-based interventions specific to LTC is

needed to tailor care delivery for this growing older population. A previous systematic review

examining evidence on infection prevention interventions in LTC have been limited to oral

hygiene and have cited a lack of strong evidence (Sjogren, Nilsson, Forsell, Johansson, &

Hoogstraate, 2008). Outbreak reports are frequently used to describe infections in this setting;

however, these reports are of limited value for assessing the effectiveness of interventions. We

found no systematic reviews which examined the utilization of planned intervention studies on

infection prevention and control in LTC. In addition, the quality of currently available evidence

is unknown. Such data are important for evaluating and developing future effective infection

prevention and control practices. Hence, the purpose of this systematic review was to critically

review and synthesize current evidence and the methodological quality of infection prevention

interventions in LTC.

Methods

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The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)

statement (Liberati et al., 2009) was used as a guide for this systematic review (see Appendix

B). PRISMA is a 27-item checklist that ensures a standard method for transparent and complete

reporting of systematic reviews and meta-analyses; it is increasingly being endorsed by and

adhered to for publication (Larson & Cortazal, 2012).

Search Strategy

Two reviewers systematically searched 3 electronic databases: Medline, PubMed, and

Cochrane Controlled Trials Register. The search terms, “infections”, “long-term care”, “skilled

nursing facilities” and “nursing home” were used in various combinations with “pneumonia”,

“sepsis”, “urinary tract infections”, “blood stream infections”, “bacteremia”, “Clostridium

difficile”, “multiple drug resistant organisms”, and “antibiotic resistant”. In addition to the

primary search, reference lists of review articles were also examined for relevant citations. Other

relevant studies were identified through expert consultation.

Selection Criteria

Type of Studies

All eligible trials had to meet the following inclusion criteria: intervention studies

published in English from January 2001 through June 2011, conducted in LTC settings (i.e.,

nursing homes) with elderly (i.e., population ≥ age 65) in which primary outcomes were

infection rates and reductions of risk factors related to infections. This 10 year time frame was

chosen because we were interested in relatively recent interventions. Excluded were editorials,

commentaries, outbreak studies and interventions in which outcomes focused only on healthcare

workers and systemic pharmacological interventions (e.g., antibiotics) other than vaccines.

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Interventions that only evaluated the efficacy or immunogenicity of vaccines were also excluded.

Additionally, we excluded interventions that were conducted solely in LTC hospitals; however

we included studies if the sample of residents included both nursing homes and LTC units within

hospitals. We considered the intervention to be therapeutic if it provided treatment to reduce the

infection being examined. For instance, an intervention evaluating the effectiveness of providing

professional oral care for preventing pneumonia was categorized under therapy. On the other

hand, an intervention that evaluated the effects of a repeated education program to improve

dental hygiene was categorized as educational.

Two reviewers (MU and MP) assessed study eligibility. First, MU independently

screened abstract titles for which MP reviewed and confirmed eligibility. Differences in

eligibility assessments were resolved by discussion between the entire review team.

Outcome Measures

The primary outcome measures were infection rates and reductions of risk factors related

to infections. For instance, studies evaluating pneumonia incidence rates were considered for

inclusion. Additionally, evaluation of outcomes such as cough reflex sensitivity, a known risk

factor for pneumonia, were included; However, studies that solely evaluated non-specific

outcomes of infections such as overall hospitalization rates, mortality and antibiotic prescription

usage were excluded since these outcomes may not necessarily be a result of infections. Our

primary outcomes were infection rates or risk factors related to infections. Therefore, we also

excluded studies even if they reported mortality as a result of an infection if they did not examine

infection rates or risk factors for getting that infection.

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Data Extraction

Data were extracted based on objectives, study design, sample size, type and duration of

interventions, outcome measures reported, and findings. Given the wide range of settings and

services provided in LTC, care variations may exist. To further characterize the context under

which the interventions were conducted, we also abstracted data by country, the number of

interventions employed, the number of facilities included in a given study and whether or not the

residents played a direct participatory role during the interventions.

Assessment of Methodological Quality

The same two reviewers independently assessed the quality of studies using a validated

tool developed by Downs and Black (Downs & Black, 1998). This quality assessment tool lists

27 criteria and evaluates both randomized and non-randomized trials. The tool, provided under

Appendix C specifically attempts to measure study quality across four domains: study reporting,

internal validity-bias, internal validity-confounding and external validity. As done in previously

published reviews using the Downs and Black tool, the original version was slightly modified for

this review (Samoocha, Bruinvels, Elbers, Anema, & van der Beek, 2010). The modified quality

assessment scores were grouped into the following 4 ratings: excellent (26 to 29), good (20 to

25), fair (15 to 19) and poor (less than 15).

Inter-rater reliability was established using a two-step process comparing independently

scored ratings. Quality scores within 2 points of each other were considered to be in agreement.

First, one study initially assessed to have the greatest score difference was reviewed to make sure

the criteria were being interpreted in the same way. Following discussion and resolving

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differences, the reviewers independently re-assessed those with score differences greater than 3.

Upon completion of this process, all studies were rated to be within 2 points from each other.

Results

Study Selection

The electronic database search yielded 1978 articles. After excluding duplicates, 1920

abstract titles were screened for eligibility. Of these, 1889 articles were excluded based on title

screening and abstract review (see Figure 2.1). The main reason for excluding studies was based

on the study design: the majority of the studies did not have an interventional component. Upon

hand searching reference lists of recent review articles and consulting a LTC expert, 3 additional

studies were included. This resulted in retrieval of 34 full text articles as potentially eligible.

Upon detailed examination, 8 studies were excluded because their primary outcomes did not

include infection rates or reduction of risk factors and 2 studies were excluded because they were

feasibility studies leading up to the larger, more recent study conducted by the same investigator.

Characteristics of Studies

Selected characteristics of the reviewed studies are presented in Table 2.1. The majority

of the studies were conducted in the United States (n= 9; 37.5%); the others were conducted in

Japan (n=7; 29.1%), Europe (n= 4; 16.7%), and Canada (n= 4; 16.7%). Overall, the majority

were randomized control trials (n= 16; 67%)(Adachi, Ishihara, Abe, Okuda, & Ishikawa, 2002;

Baldwin et al., 2010; Banting & Hill, 2001; Gornitsky, Paradis, Landaverde, Malo, & Velly,

2002; Liu et al., 2007; Maruyama et al., 2010; McElhaney et al., 2004; Meurman, Parnanen,

Kari, & Samaranayake, 2009; Meydani et al., 2004; Mody, Kauffman, McNeil, Galecki, &

Bradley, 2003; Nishiyama, Inaba, Uematsu, & Senpuku, 2010; Trick et al., 2004; Washington,

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2001; Watando et al., 2004; Wendt et al., 2007; Yoneyama et al., 2002), where the primary

interest was to reduce respiratory infections (n=15; 62.5%) and focused on interventions that

provided therapy (n= 17; 70.8%) as opposed to being educational.

Of the 15 studies that examined respiratory conditions, pneumonia was the most

commonly reported infection (n=12; 50%), and the most common intervention was oral hygiene.

Of the 16 randomized trials, one study (Quagliarello et al., 2009) was a feasibility study but was

included because no subsequent analysis by the same investigator was available. Eight studies

(Fendler et al., 2002; Hutt et al., 2010; Ishikawa, Yoneyama, Hirota, Miyake, & Miyatake, 2008;

Kullberg et al., 2010; Mody, McNeil, Sun, Bradley, & Kauffman, 2003; Quagliarello et al.,

2009; Thai, Keast, Campbell, Woodbury, & Houghton, 2005; Yamada, Takuma, Daimon, &

Hara, 2006) were quasi-experimental in nature but varied in terms of design complexity. For

instance, Kullberg and colleagues (Kullberg et al., 2010) examined an oral hygiene education

program using a single site pre-posttest design, while Ishikawa and colleagues (Ishikawa et al.,

2008) examined the impact of professional oral cleaning across multiple sites using three

interventions.

Across the 24 studies, 12 studies (50%) had more than one component to the intervention,

and more than half (n= 15; 62.5%) were conducted at multiple LTC facilities. Approximately

three fourths of the studies required direct resident participation during the interventions (n= 18;

75%), whereas, a quarter of the studies tested interventions on healthcare workers, yet still

evaluated resident infection outcomes (e.g., hand hygiene studies).

Most studies (n= 21; 87.5%) compared two study groups: an intervention group receiving

an infection prevention or risk factor reduction treatment, and a control group receiving usual or

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no care. Examples of exceptions were those in which 3 dental brand cleansers were compared

(Gornitsky et al., 2002) or two solutions to irrigate urinary drainage bags were compared with

water as the control (Washington, 2001).

The frequency of interventions varied across all and within similar intervention studies

ranging from weekly to as long as 1 year. Additionally, the duration of the follow-up

measurements varied from 4 days to longer than a year. Furthermore, differences were found in

the content level of similar interventions. For instance, two quasi-experimental studies(Fendler et

al., 2002; Mody et al., 2003) evaluating the impact of alcohol based hand sanitizers on

nosocomial infection rates provided hand sanitizers to healthcare workers in one facility. While

Mody and colleagues (2003) conducted a multimodal intervention (i.e., baseline questionnaires,

3 week basic hand hygiene education for both groups, and 12 week education period for

intervention group), Fendler and colleagues (2002) provided hand sanitizers and instructed staff

on usage at the time of distribution.

Participants

Sample sizes varied and ranged from 20 to 1,006 residents; four studies had sample sizes

less than 50. For those studies that did not require direct resident participation during the

interventions, sample size was often not reported; instead, for example, investigators reported 16

nursing home units as their sample population.

Outcomes

Thirteen (54%) of 24 studies reported statistically significant results in favor of

interventions on at least one of their outcome measures. Of the 9 studies reporting infection rates,

respiratory infection rates were explicitly mentioned in 5 studies (Fendler et al., 2002; Maruyama

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et al., 2010; McElhaney et al., 2004; Meydani et al., 2004; Yoneyama et al., 2002). All other

studies measured one or more infection risk-related outcomes: 8 studies measured oral bacteria

(e.g., number of colony forming units, plaque scores, presence of Candida albicans); one study

measured bacteriuria; one study measured vaccination rates; 4 studies evaluated acquisition and

or eradication of multiple drug resistant organisms; 5 remaining studies measured outcomes such

as cough reflex sensitivity and nosocomial infection rates without further specification.

In general, there was no standardized definition used to examine infection rates. While

many studies defined an outcome measure, they varied in terms of how infections were

confirmed—using clinical judgment, radiographs, other laboratory tests or all three. Three

studies explicitly (Fendler et al., 2002; Lona Mody et al., 2003)or indirectly(Liu et al., 2007)

mentioned using nosocomial infection definitions derived from the McGeer criteria (McGeer et

al., 1991), a guideline used for defining infections in LTC. One study (Mody et al., 2003)

reported to monitor S. aureus infections based on the Centers for Disease Control and Prevention

definitions, whereas another study reported to have developed their own clinical definitions of

pneumonia and incorporated some of the McGeer criteria (Meydani et al., 2004).

Methodological Quality of Studies

The methodological quality of the available evidence varied, and none of the included

studies fulfilled all Downs and Black criteria, with quality scores ranging from 11 to 27 out of 29

possible points (mean: 18.8). The largest proportion of studies (n= 9; 37.5%) were rated as ‘fair’

quality. Alternatively, 7 studies were rated good and only 3 studies had excellent quality. Five

studies received a score of 15 or less indicating poor quality. A frequently observed weakness

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was a lack of power analysis. In 10 of the 16 randomized studies, the randomization method and

allocation concealment measures were not adequately described.

Discussion

The interventions audited for this review varied considerably in terms of their content,

intensity, and duration. Definitions used for infections had substantial variability, making

between-study comparisons difficult. Particularly problematic was the lack of clarity in

definitions of outcome measures; some studies used clinical assessments alone whereas others

included laboratory indicators. Despite the wide gaps, some critical insights and meaningful

patterns have emerged from among these recent interventions.

First, the majority of interventions were randomized control trials. This was surprising

given the nature of LTC settings. Since the residents live within the same facility, it is often not

feasible to blind the residents or healthcare workers caring for the residents. In many of the

studies reviewed, proper allocation concealment was absent, leading to lower overall quality

ratings and potential risks of bias. If future interventions are to be implemented under current

LTC structures (i.e., residential setting, socializing between residents) adequate study methods to

blind the researchers, data analysts and statisticians should still be done; additionally, studies

could utilize cluster randomized trial designs which can reduce some of the risks of bias within

studies.

Second, despite the high prevalence reported in LTC, few interventions specifically

targeted UTIs. Of the reviewed studies, only one study (Washington, 2001) carried out an

intervention to reduce bacterial counts in urinary drainage bags and two studies (Fendler et al.,

2002; Liu et al., 2007) reported UTI rates in aggregate as part of the larger evaluation of

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nosocomial infection rates. The frequency of therapeutic interventions focusing on oral hygiene

is not surprising given the known prevalence of pneumonia in LTC. However, more studies need

to evaluate interventions aimed at other types of infections on the rise such as multi-drug

resistant organisms.

Finally, only one study (Trick et al., 2004) explicitly addressed the costs of conducting

the intervention. With the increasing cost of healthcare being a focal policy issue, there is serious

need to pair current effectiveness data with economic evaluations. Cost-effectiveness analysis

complements clinical evidence evaluation and is increasingly used to guide institutional and

public policy decisions (Weinstein & Skinner, 2010). Few economic analyses of infection

prevention strategies have been conducted in LTC (Trick et al., 2004). More economic evidence

is needed to guide future decisions in LTC that are tailored for this population.

Limitations

This review has several limitations. Only English-language articles published in peer-

reviewed journals after 2001 were included. Limiting our search to publications after 2001,

however, is justified given the dramatic changes in infection prevention and control over the past

decade7. By including only published papers, we realize that publication bias may exist.

However, given that many of the studies reported non-significant findings, we do not think this is

likely. Attempts were made to be comprehensive in the search strategy; however, because our

selection criteria had a narrow focus, this may have resulted in exclusion of some effective

interventions. For instance, we realize that many intervention studies in LTC have focused on

healthcare workers and their rates of vaccinations and hand-hygiene compliance. Additionally, it

is important to note that older adults can reside in LTC settings other than nursing homes. For

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instance, we excluded other extended care settings such as psychiatric institutions where the

residents are typically much younger than nursing home residents (Smith et al., 2008).

Furthermore, the exclusion of outbreak reports may have led to missing interventions developed

during these types of events.

Implications for Practice and Future Research

Gaps and inconsistencies surrounding infection prevention interventions in LTC are

evident. In general, the quality of evidence surrounding these interventions is weak. Valid data

regarding infection rates and risk reduction strategies are essential for guiding surveillance and

practice decisions. Perhaps most relevant, such data are vital to inform nursing home

administrators and policymakers that infection prevention strategies are as important in LTC as

in hospitals for improving patient safety and quality of care. Infections in LTC, particularly those

associated with multi-drug resistant organisms, are of major importance to the entire healthcare

system because of the frequent transition of patients between the LTC and acute care settings.

To promote clarity in reporting of infection prevention interventions, future researchers

and clinicians conducting such interventions should follow standardized protocols. One way of

ensuring adequate reporting is to use existing publication guidelines endorsed by major

biomedical journals such as the consolidated standards of reporting trials (CONSORT

http://www.consort-statement.org/) for randomized control trials and the transparent reporting of

evaluations with nonrandomized designs (TREND http://www.cdc.gov/trendstatement). Both

guidelines, CONSORT, originally published in 2001 and most recently updated in 2010 and

TREND, published in 2004 were developed to improve clarity and consistency of reporting

research. In a review by Larson and Cortazal (Larson & Cortazal, 2012) the extent to which these

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guidelines have been adopted for use in peer-reviewed publications varied. In their analysis, they

found 565 PubMed citations using CONSORT, while only 5 studies were retrieved using

TREND. Considering the frequency in which non-randomized studies are used in infection

prevention and control studies, the relatively low uptake of TREND for reporting non-

randomized interventions is concerning. Additionally, other researchers have cited the need to

use a more standard nomenclature to describe non-randomized interventions by uniformly

referring to pre-post intervention studies as quasi-experimental to avoid confusion (Harris,

Lautenbach, & Perencevich, 2005). In our analysis, of the 24 studies published after 2001, only

one randomized trial (Baldwin et al., 2010) reported using the CONSORT statement or other

similar publication guidelines.

On the basis of our review, we recommend the adoption of existing publication

guidelines to assist in establishing clarity and consistency across future interventional studies.

Adoption of these guidelines should be embraced by journal authors and editors as a part of

standard practice for reporting research. We refer readers to the Resource Center on Enhancing

the QUAlity and Transparency Of health Research (EQUATOR http://www.equator-

network.org/resource-centre/library-of-health-research-reporting/) Network for a complete list of

currently available reporting guidelines as it expands on CONSORT, TREND, PRISMA and

other reporting guidelines for various types of research designs.

Conclusion

Infection prevention in LTC facilities is an increasingly important area of research and

yet significant gaps exist in the quality of interventions currently reported. Future researchers and

practitioners in LTC need to establish a comprehensive understanding of accurate and consistent

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measures for enhancing methodological clarity using clearly defined outcome measures and

standardized reporting of findings. With increased attention surrounding potentially avoidable

infections, more high quality interventions will need to be tested to solve the complicated

problems of infection prevention and control in LTC.

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Table 2.1:

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Figure 2.1:

Flow Diagram

Articles eligible for final inclusion in this review n= 24

Full text articles retrieved for detailed evaluation n= 34

Articles excluded: based

on inclusion criteria n= 8,

feasibility studies by the

same author n=2

Articles excluded per title

screening and abstract

review based on inclusion

criteria n= 1889

Articles identified in PubMed, Medline-OVID and Cochrane

Controlled Trials Register n= 1978

Abstracts screened for eligibility n= 1920

Articles excluded based

on removal of duplicates

n= 58

Articles included per hand searching reference lists, expert consultation n= 3

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Chapter 3: Quantitative Analysis

In this chapter, the effects of various nurse workforce characteristics on resident

outcomes in VA CLCs were examined. A six-year panel of monthly, unit-specific data were

analyzed which included nurse workforce information, resident characteristics and resident

outcome measures. Descriptive statistics and unit-level fixed effects regressions were conducted.

This paper was submitted to the Journal of the American Medical Director’s Association.

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Abstract

Objective: To examine effects of workforce characteristics on resident infections in Veterans

Affairs (VA) Community Living Centers (CLCs).

Data Sources: A six-year panel of monthly, unit-specific data included workforce characteristics

(from the VA Decision Support System and Payroll data) and characteristics of residents and

outcome measures (from the Minimum Data Set).

Study Design: A resident infection composite measure was the dependent variable. Workforce

characteristics of registered nurses (RN), licensed practical nurses (LPN), nurse aides (NA), and

contract nurses included: staffing levels, percentage of hours worked and tenure. Descriptive

statistics and unit-level fixed effects regressions were conducted. Robustness checks varying

workforce and outcome parameters were examined.

Principal Findings: Average nursing hours per resident day was 4.59 hours (sd = 1.21). RN

tenure averaged 4.7 years (sd = 1.64) and 4.2 years for both LPN (sd= 1.84) and NA (sd= 1.72).

In multivariate analyses RN and LPN tenure were associated with decreased infections by 3.8%

(IRR= 0.962 p<0.01) and 2% (IRR=0.98 p<0.01) respectively. Robustness checks consistently

found RN and LPN tenure to be associated with decreased infections.

Conclusions: Increasing RN and LPN tenure are likely to reduce CLC resident infections.

Administrators and policymakers need to focus on recruiting and retaining a skilled nursing

workforce.

Key Words: Nursing homes, quality, staffing, infections

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Introduction

Nursing home (NH) services account for a major segment of the United States healthcare

delivery system. Among the 1.5 million residents living in the nation’s 16,000 NHs (Jones,

Dwyer, Bercovitz & Strahan, 2009), poor or variable quality of care has been reported to

negatively impact resident outcomes (Bostick et al., 2006; Castle, 2008; Castle & Engberg, 2007;

Konetzka, Stearns & Park, 2008). Of these outcomes, increasing attention has been focused on

reducing infections (U.S. Department of Health and Human Services, 2013).

For NH residents, infections are a leading cause of morbidity and mortality despite often

being preventable (Richards, 2007). Infections are also the most common reasons for

hospitalizations, accounting for 27 to 63 percent of all resident transfers (Barba, 2011; Teresi et

al., 1991). Recently, it was reported that 15 percent of the nation’s NHs received annual

deficiency citations for infection control, and low nurse staffing levels in NHs were positively

associated with these citations (Castle, Wagner, Ferguson-Rome, et al., 2011). While

associations between increased nurse staffing levels and decreased resident adverse outcomes

such as urinary tract infections (UTIs) and pressure ulcers (PUs) have been found in a number of

NH studies, much of this work has been cross sectional or limited by the inability to track nurse

staffing beyond NH facility levels (e.g., not specific to a NH unit) (Kim, Harrington & Greene,

2009; Konetzka et al., 2008). Furthermore, focusing on nurse staffing levels alone ignores other

important characteristics of the workforce such as experience and percentage of hours worked by

various nurse types (Bartel et al. in press). While physicians take part in managing some of the

services, the majority of care in NHs is provided by nursing personnel. Relative to acute care

settings, which have a higher proportion of registered nurses (RN), NHs employ more licensed

practical nurses (LPN), and nursing assistants (NA)(Harrington, 2005a). Understanding how this

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workforce provides safe, high quality care to the nation’s rapidly growing NH population is

critical.

Using a six-year panel of monthly, unit-specific data from the Department of Veterans

Affairs (VA), this study examines the effects of various nurse workforce characteristics on

infection outcomes as a function of resident quality of care in Community Living Centers

(CLCs), formerly known as VA Nursing Homes.

Background

Previous researchers have examined relationships between staffing and quality outcomes

in NHs (Castle & Anderson, 2011; Castle & Engberg, 2007; Harrington, 2012; Harrington,

Swan, & Carrillo, 2007; Hickey et al., 2005; Kim et al., 2009; Konetzka et al., 2008). However,

none have examined this relationship in the VA specifically addressing infections.

Focus on improving resident safety and quality is a top priority in the VA (GAO, 2006,

2011). As the largest single provider of healthcare in the U.S., as of 2011 the VA operated 133

CLCs across the country and provided care to more than 46,000 veterans annually (GAO, 2011).

The VA CLC system is part of the spectrum of long-term care that provides a skilled nursing

environment and houses a variety of specialty programs for veterans requiring short (<90 days)

and long stay (>90 days) services (Department of Veterans Affairs, 2005, 2008). The VA CLCs

are typically located on, or within close proximity to a VA medical facility. While some veterans

receive NH services in private sector settings, this study only examined nursing care actually

provided in VA owned and operated facilities (i.e., excludes state veterans homes and non-VA

NHs in which a veteran may be admitted).

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Due to lack of access to unit-specific data, several past studies that examined nurse

workforce characteristics used the facility as the unit of observation (Castle, 2008). For example,

using administrative datasets such as the Online Survey Certification and Reporting System

(OSCAR), an annual survey collected every 9 to 15 months through the Centers for Medicare

and Medicaid (CMS), only allows resident and nurse staffing data to be traced to the facility

level and information on nurse staffing is self-reported (Rantz & Connolly, 2004). Using facility-

level measurement of staffing can be a disadvantage especially when attempting to link staffing

to the resident point of care. Compared to facility-level data, staffing data at the unit level will

more likely detect differences in resident populations and represent a more accurate picture of

resident case-mix.

Although it may seem that the individual nurse caring for the resident on any given shift

should be analyzed, development of adverse outcomes such as infections or PUs are most likely

cumulative and often cannot be attributed to one nurse or work shift in time. Therefore, the

primary unit of analysis for this study was monthly unit-level staffing and resident data across a

national sample of VA CLCs.

Conceptual Framework

This study was guided using an adapted framework of quality proposed by Donabedian

(1966). According to Donabedian, quality healthcare is defined along three basic dimensions:

structures, processes, and outcomes. In his seminal work, Donabedian defines the structures of

care as administrative and related processes that support and direct the provision of care,

including the regulatory environment and human resources. The processes of care are the actions

or services involved with direct provision of care. The outcomes of care are the consequences or

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results that can be attributed to the structures and processes (i.e., infections). Based on this

framework, a conceptual model was developed (see Figure 3.1). The structures of care are the

characteristics associated with the CLC unit and the nurse workforce (e.g., nurse staffing levels).

The processes of care relate to the care services provided on the unit (e.g., ventilator use). The

extent to which these structural and process characteristics impact resident adverse outcomes in

VA CLCs is currently unknown.

Objective

The main objective of this study was to estimate the effects of various nurse workforce

characteristics on changes in resident infection related adverse events in VA CLCs. The

following hypotheses were examined:

Hypothesis 1: Controlling for resident and unit characteristics, as nurse staffing hours of care

increase, the risk of resident infection outcomes will decrease.

Hypothesis 2: Controlling for resident and unit characteristics, as the percentage of hours

worked by RNs increase, the risk of resident infection outcomes will decrease.

Hypothesis 3: Controlling for resident and unit characteristics, as nurse tenure on a unit increase,

the risk of resident infection outcomes will decrease.

Methods

This study is a retrospective secondary analysis of data collected for a larger study

examining VA CLC nursing care quality and resident safety (RWJF #63959). An existing

longitudinal, unit-level dataset of VA CLC residents and nurse workforce data from fiscal years

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2003-2008 (October 2002 to September 2008) was examined. Institutional review board

approval was obtained from both Columbia University Medical Center and Stanford University.

Data Sources

Data came from three major sources: first, from the VA Decision Support System (DSS)

national data extracts; second, from the VA payroll data (PAID); and third, from the Minimum

Data Set (MDS) Resident Assessment Instrument. Other sources included VA administrative

files for facility information and the VA Vital Status Mini File for age and gender. Nurse

workforce characteristics came from the DSS and PAID. Characteristics of CLC residents and

outcome measures came from the MDS. An overview of the variables, definitions, and the data

sources from which these variables were constructed is provided in Table 3.1. Detailed

descriptions of the 3 major data sources and justification for our variables follow.

VA Decision Support System (DSS)

DSS is VA’s integrated accounting system. Within the DSS, several layers of data exist.

First, monthly data on nursing hours were obtained from the DSS Account Level Budgeter Cost

Center (ALBCC) and Account Level Budgeter Hours (ALBHR). The ALBHR tracks nursing

personnel hours appropriated to each unit by the type of labor (e.g., RN or LPN). While the

ALBHR includes hours for regular staff, the use of contract labor (agency nurse) was only

captured in the ALBCC files. By adding the contract nursing hours to the ALBHR files, we were

able to obtain the monthly total number of nursing hours worked on each unit to create the

numerator for our staffing hour variables. Another layer of DSS data is the Inpatient Ward Files,

which tracks the patient admission and discharge dates of each nursing unit. This file was used to

create unit characteristic variables such as the total number of admissions on the units.

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VA Payroll Data (PAID)

Nurse workforce characteristics for tenure were obtained from PAID. The PAID data

includes employee information such as VA hire date, when the staff started at their current unit,

and the type of nursing position.

Minimum Data Set (MDS)

Resident characteristics and outcomes data came from the MDS Version 2.0, a

government mandated resident assessment tool. It serves as a core component of the resident

assessment instrument and is used to collect information on clinical and functional status

elements of all NH residents in facilities certified to participate in Medicare or Medicaid and in

VA long-term care programs accredited under the Joint Commission on Accreditation of

Healthcare Organizations. Residents are assessed on admission, quarterly, annually and at times

of significant change in status. In non-VA settings, the MDS is used to determine Medicare

reimbursement rates as a function of residents’ assignment to resource utilization groups (RUG).

While VA CLCs do not operate under this system, per diem reimbursement of individual CLC

units is based in part on timely completion of MDS assessments and therefore all VA CLCs have

recorded MDS data since 1998 (GAO, 2004).

Data Preparation

All resident-level and nurse workforce data were de-identified and aggregated to the unit-

month level. Unique facility identifiers were used in combination with ALBCC codes to identify

VA CLC units used in our analyses.

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To minimize erroneous data, outliers were removed. Based on data distribution, we first

excluded observations where the monthly total RN hours (worked and overtime) less than 240

hours or resident days less than 180. If 50 percent or more of the observations for a unit were

excluded from that process, then the unit was excluded. While previous studies report excluding

observations with total nursing hours per resident day less than 0.5 hours and greater than 12.0

hours(Konetzka, Yi, Norton, & Kilpatrick, 2004; Wan, Zhang, & Unruh, 2006), we excluded

total nursing hours per resident day less than 2.0 hours and greater than 8.0 hours because VA

CLCs have traditionally been known to have higher staffing than the private sector (National

Commission of VA Nursing, 2004) and those data appeared to be the outliers in our sample.

Operationalization of Variables

The following variables come from unit-specific aggregated data representing the number

of residents or resident days per month.

Outcome Variables

The CMS list UTI, pneumonia and PUs to be among the top chronic-care quality

indicators in NH care (Morris et al., 2003). Even though PUs are not considered to be an

infection, they reflect important and frequent occurring events in the NH setting and can

potentially develop to become infectious and therefore were included (Gruneir & Mor, 2008).

Our primary outcome variable was a composite of resident infections defined as the summation

of three outcomes (i.e., UTI, pneumonia, and PUs). Use of composites can compensate for the

relatively low rates of individual infections and can therefore increase power. Composites also

serve as important indicators of safety and quality improvements and have been increasingly

reported in the literature and used in research (Physician Consortium for Performance

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Improvement, 2010; Rosen et al., 2013). While we also examined each of the infection outcomes

separately, we report a composite of infections because all of these outcomes indicate adverse

events that interrupt residents’ quality care.

The MDS was used to determine the various infection outcomes. To avoid counting

outcomes present on admission, MDS assessments coded as admissions were excluded. Because

some MDS assessments were incomplete or had missing data, those assessment types were also

excluded. Rates for the composite measure were calculated as adverse outcomes per 1,000

resident days. A resident day is defined as 24 hours of care starting the day of admission and

excluding the day of discharge. In other words, the sum count of infections was our numerator

and total resident-days were our denominator.

Independent variables

Nurse workforce characteristics were our main independent variables of interest and

measured using 3 conceptual categories: nurse staffing levels, percentage of hours worked by

nurse type, and nurse unit tenure. Nurse staffing level was operationalized as nursing hours per

resident day (HPRD). Nursing hours included the total number of hours worked (regular and

overtime) either by RNs, LPNs, NAs, and contract nurses. To represent the total nursing hours of

care per resident day (Total Nursing HPRD), we added the total number of hours worked for all

staff and divided it by resident days.

Percentage of hours worked was measured as a function of RNs, LPNs, NAs and contract

nurses. Percent RN was operationalized as RN worked hours as a proportion of total staffing

hours (RN, LPN, NA, and contract nurses combined). LPN, NA and contract nurse percent hours

measures were also constructed similarly. While total nursing HPRD measures the extent of

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nursing hours available to provide resident care, the percent nursing hours variables characterize

the extent to which different staffing expertise may be available on a unit to carry out specific

care processes or shift tasks of care (Clarke & Donaldson, 2008).

Nursing experience was measured by unit tenure, defined as the number of years RNs

LPNs, and NAs had worked on the unit. Contract nurse tenure information was not available in

this dataset.

Process Variables

Guided by previous NH literature examining resident quality of care, the proportion of

residents using indwelling urinary catheters and ventilator support were included as process

measures (Thomas, Mor, Tyler & Hyer, 2013). To capture care processes specific to PUs, the

proportion of residents on a turning/repositioning program was included. For each variable, the

numerator was the count of these processes in place and the denominator was the total resident

population.

Covariates

Two types of control variables were considered to impact care quality: resident and unit

characteristics. First, to control for any differences in risk for infections, several time varying

covariates were included (Hyer et al., 2011; Thomas et al., 2013). Resident characteristics

included age, gender, race, dependence in activities of daily living (ADL), and presence of

cognitive impairment. Age was defined as the average age of residents on the unit. While the

majority of the VA CLC population is known to be male, female veterans also reside on these

units (GAO, 2006). Gender was defined as the proportion of male residents on the unit. To

control for race, as done in previous work (Thomas et al., 2013), the percent of residents

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identified as black, non-Hispanic were included. An ADL index was calculated based on the

mean value of resident functional limitations across 3 activities (eating, toileting, and

transferring). Cognitive impairment was defined as the percent of residents with either

Alzheimer’s disease or other dementia diagnosis.

A set of unit characteristics likely to affect outcomes was also included. The number of

admissions received during the month of observation represents the unit volume. The RUG

scores represent the average case-mix severity. Higher RUG scores indicate greater resident care

needs. The percent of residents expected to have a short-term stay (<90 days) represented the

unit composition of shorter stay residents. MDS data were used to create this variable, but

because MDS data were only available beginning fiscal year 2003, to avoid underestimating the

percent of residents expected to have a short-term stay, the first quarter of fiscal year 2003

(October, November and December) was dropped from the analyses.

Data Analysis

Main Analysis Methods

Descriptive statistics and bivariate correlations were examined. Monthly unit-level

multivariate fixed effects models were developed. Based on the infection composite distribution

(variance exceeded the mean), the negative binomial model was used. In addition to the time

variant covariates listed earlier, time trends were controlled for using a set of monthly time

dummy variables. Regression diagnostic statistics such as the variance inflation factor (VIF)

were examined. Analyses were performed with STATA 12.0 (College Station, TX).

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Prior to the multivariate analyses, a preliminary correlation matrix was constructed for all

nurse workforce variables (results not shown). As expected, there was high correlation between

RN HPRD and Percent RN (r= 0.78 p<0.01). Because our objective was to simultaneously

examine indicators of staffing levels, percentage of hours worked and experience, we used a

model that allowed measures from all 3 nurse workforce categories. Therefore, we retained only

Total Nursing HPRD to represent nurse staffing levels. To avoid collinearity among the

percentage of hours worked by nurse type, we excluded the percent LPN variable and treated it

as the reference variable. The proportion of residents with urinary catheters is provided under

descriptive statistics but was not included in the multivariate model because of convergence

problems.

Robustness Checks

Two alternative models were examined to determine the robustness of the results. First,

the various nurse workforce characteristics were lagged to examine whether staffing

characteristics in the month prior (t-1) had an influence on outcomes observed in the current

month (t). Second, because MDS assessments are not conducted monthly, we risk the potential

sampling bias of not capturing all resident infections in the numerator. Because the dependent

variable of our study was the sum of resident infection outcomes (counts), and were non-

negative integers, early in our data preparation stage, we adopted the Poisson distribution

because it is a widely used non-linear distribution of count data. We then used the Poisson

pseudo-random number generator to pull forward infection outcomes recorded in the month of

observation until the residents’ next MDS assessment or whenever there was a significant change

in status and or when the infection was no longer recorded. Because our analyses assume that

NH quality is based on unobservable heterogeneity that vary across CLC units but remain

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constant over time, we also developed and examined alternative assumptions with random

effects and population averaged models. A Poisson fixed effects was also conducted to check our

underlying distribution assumptions.

Results

The final sample included 180 units across a national sample of 84 CLCs (10,611 unit-

monthly observations). Facilities included in our final sample came from 20 out of the 21 total

VA integrated networks (VISN) across thirty-seven states.

Descriptive Statistics

Table 3.1 shows the descriptive statistics for the variables used in the analysis. A detailed

table on all nurse workforce characteristics is provided in Appendix D. Average nursing HPRD

was 4.59 hours (sd= 1.21). Percentage of nursing hours worked by RNs, LPNs, NAs, and

contract nurses were 31.3%, 25.8%, 41.5%, and 1.5% respectively. Unit tenure averaged 4.7

years for RNs (sd= 1.64) and 4.2 years for both LPNs (sd= 1.84) and NAs (sd= 1.72). Average

unit tenure combined for the 3 staffing types was 4.3 years. Pairwise correlations of all the

independent variables used in the model are shown in Appendix E. Nurse workforce

characteristics included in our final model were not highly correlated, with the highest

correlation (-0.56) found between Percent RN and Percent NA. Using these variables, multi-

collinearity was assessed using the VIF test. Across all the variables, VIF values were lower than

10 which indicated no multi-collinearity (overall mean VIF 1.48).

Composite Measure of Resident Infection Outcomes

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Table 3.2 presents the coefficient estimates for our main model. To facilitate

interpretation, all coefficients have been exponentiated and can be interpreted as the incidence

rate ratio of having infection outcomes. Both RN and LPN unit tenure were significant

independent predictors of the infection composite. Results indicate that for every one year

increase in unit tenure, the incidence of infections decreased by 3.8% for RNs (IRR= 0.962

p<0.01) and 2% for LPNs (IRR=0.980 p<0.01) while controlling for all other variables in the

model. That is, an increase in one year of RN tenure within a unit was associated with 38 fewer

infections for every 1,000 resident days. Ventilator use and those residents on

turning/repositioning program were associated with increased likelihood of infections. Some of

the resident and unit characteristics also had independent effects; increase in mean ADL index

was positively associated with an increase in infections (IRR=1.03 p<0.01); average case mix

severity on a unit represented by RUG scores was related to a more than five-old increase in

likelihood of developing infections (IRR= 5.77 p<0.01). Finally, on average, a unit with a higher

proportion of residents expected to have a short-term stay had an increased likelihood of

infections (IRR= 3.01 p<0.01).

Robustness Checks

Results from the robustness check are displayed in Table 3.3. In the lagged staffing

model, RN and LPN tenure was associated with a lower incidence rate of infections (3.8%,

p<0.01 and 2%, p<0.01 respectively). Similarly, when pneumonia counts were pulled forward in

time, the results were very similar compared to when the infection was only counted in the

month of observation. Additionally, increasing Total Nursing HPRD contributed to 3.9%

reduction in pneumonia incidence (p<0.05). When we varied the models using random effects

models and population average models, the results were robust to the different assumptions and

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were consistently significant for RN Tenure, but not LPN Tenure. While some differences exist,

the coefficient parameters and standard errors are very similar; the Hausman test comparing the

fixed effects model to the random effects model showed results in favor of the fixed effects

model (p<0.001) (see Appendix F, Technical Appendix 1).

Discussion

Our findings suggest that one way to reduce the occurrence of resident infection

outcomes is to target and minimize RN and LPN turnover on the units. To the best of our

knowledge, this is the first study to use unit-specific longitudinal panel data to examine

relationships between a comprehensive set of nurse workforce characteristics and infection

outcomes in the VA CLCs. In a recent VA acute care study, increases in the average tenure of

RNs was found to result in significant decreases in the length of time patients stayed in the

hospital (Bartel et al. in press).

The rationale to use a fixed effects model was to estimate the within-unit effects of

various nurse workforce characteristics associated with the changes in our composite measure of

resident infection outcomes across time. This within-unit analysis controls for time invariant

unobservables. For example, each unit could have its own unique organizational culture or

communication style that would rarely change and may affect the outcomes of care. A CLC unit

with a “good” nurse manager could impact staff motivation to improve outcomes versus a CLC

unit with a “bad” nurse manager. Because we do not have measures in our dataset to control for

such instances, omitting such unobserved individual unit specific variables may create bias in the

estimation of our outcomes in a non-fixed effects analysis (Sochalski et al. 2008). While one

could debate whether the fixed effects approach was appropriate or not, it ultimately depends on

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the assumptions one is willing to take into account (Setodji & Shwartz, 2013) and because our

interest was to estimate the within-unit variation which controls for unobserved variables that do

not vary by month, we believe our reasons to use a fixed effects model are justified. Further, our

results were very robust to model specification.

As expected VA staffing was higher than the private sector. While 4.1 hours of total

nursing HPRD for long-stay NH residents has been recommended by CMS (CMS, 2001), in our

sample average total nursing HPRD was 4.59 hours exceeding recommendations of an expert

panel which called for 4.55 hours (Harrington et al., 2000). Assuming diminishing returns and

the fact that other studies have shown that it is really short staffing that matters, it is not

surprising that we did not find a robust staffing effect.

Implications for Policy and Practice

Most importantly, these results suggest that tenure, especially skilled nurse unit tenure is

important for decreasing resident infection outcomes in CLCs. It also implies that in a NH

setting, it may not be only the quantity of the nurses or hours of care that matters in preventing

infections, but how well the nurse with supervision responsibilities is familiar with the residents

and of the unit. Practice implications for NH administrators and policymakers would therefore be

to recruit and retain an experienced RN and LPN workforce on NH units. To ensure a stable

supply of RNs and LPNs, emphasis should first be placed on educating and supporting the

current skilled workforce to prevent turnover. Institutional awareness or ongoing support in the

area of infection prevention and control could be used to enhance training of an adequate RN and

LPN workforce.

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Strengths and Limitations

This study has several important strengths that extend existing research. First, unlike

previous cross-sectional studies that only examined nurse staffing levels or percent of hours

worked, we used 6 years of nationwide data and included an additional conceptual variable,

nurse unit tenure. Second, the dataset provides a unique opportunity to longitudinally examine

nurse workforce characteristics on resident infection outcomes because the CLC units belong to

the same umbrella organization that standardizes data collection across all units. This helps

overcome some of the weaknesses encountered in previous studies such as variations in data

reporting for nurse workforce measures. Third, we measured nurse workforce characteristics at

the nursing unit level rather than at the facility level. Last, because the nurse workforce data

come from payroll data, they are likely to be more accurate than other data sources.

This study also has limitations. Because we lacked access to clinical data we had to rely

on the MDS to abstract resident characteristics and outcomes. We realize that use of large

administrative data may be subject to coding inaccuracies and are not designed specifically for

research. However, previously published studies in the VA have used the MDS to examine CLC

resident outcomes (French et al., 2007). Furthermore, validity and reliability of this data source

in the VA has been established previously (Frakt, Wang, & Pizer, 2004).

The infection composite may not reflect true quality of care and we did not perform

psychometric testing (e.g., principle factor analysis) to take into account the weighting of

individual factors as done by others (Shwartz et al., 2013). This was necessary since we did not

have individual level dataset; however, effort was made to group frequently occurring outcomes

in NHs. Additionally, by using an aggregate infection composite, we may have double counted

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infections from the same resident (i.e., one resident could have both a PU and a UTI in the same

MDS assessment); However, robustness checks using pneumonia counts pulled forward in time

using the Poisson pseudo random number generator showed results that were similar to our main

analytic model. Future analyses could use individual level resident data to more accurately

capture the relationship between nurse workforce characteristics and resident infections. If

individual data are used, other analytic methods such as survival analyses can be further explored

to estimate the individual resident’s time to acquiring an infection outcome.

Finally, this study was conducted in the VA and may not be generalizable to non-VA NH

units. In addition, these results may not be transferrable to younger Veterans residing in CLCs

because they are underrepresented in our sample. Further, VA tenure levels are high compared to

the private sector and therefore marginal impact of changes in tenure could be different at lower

levels of tenure.

Conclusion

Examining nurse workforce characteristics on resident quality of care generated results

that have partially supported our hypothesis: As tenure of skilled nurses on a unit increase, the

risk of resident infection outcomes will decrease while controlling for resident and unit

characteristics. This adds to a rather large body of literature conducted over the past several

decades also examining nurse staffing characteristics and resident outcomes. Moreover, our

findings for RN and LPN unit tenure were robust, which calls for greater attention from NH

administrators and policymakers to be directed towards recruiting and retaining a qualified

skilled nursing workforce.

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Figure 3.1: Adapted Model of Healthcare Quality

Resident Characteristics

• Demographics • Functional

Status

Structures of Care

• Unit Characteristics • Nurse Workforce

Characteristics

Outcomes

• Infection-related adverse events

Processes of Care

• Catheter use • Ventilator use

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TTable 3.1: Characteristics of

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Table 2.2: Effects of Staffing on Infection Composite (UTI, pneumonia, pressure ulcer)

Outcome:

Infection Composite

Coefficient (IRR)

SE p

Total Nursing HPRD 1.000 0.010 0.985 Percent RN 1.233 0.232 0.264 Percent NA 1.160 0.180 0.336 Percent Contract 0.986 0.205 0.947 RN Unit Tenure **0.962 0.008 0.000 LPN Unit Tenure **0.980 0.007 0.006 NA Unit Tenure 1.008 0.009 0.340 Male 1.467 0.407 0.167 Age 0.999 0.004 0.865 Race 1.161 0.161 0.282 RUG **5.770 0.636 0.000 ADL Index **1.070 0.008 0.000 Percent Short Stay **3.057 0.133 0.000 Admissions **0.994 0.001 0.000 Percent Dementia 1.067 0.107 0.520 Percent Turn **1.250 0.086 0.001 Percent Ventilators **42.106 59.582 0.008

Notes. N= 10,611; IRR= Coefficients are Incident Rate Ratios; SE= Standard errors; p= p-values * Significant at p<0.05 **Significant at p<0.01 Infection Composite= urinary tract infections, pneumonia, and pressure ulcers. HPRD= Hours per resident day, RN= Registered Nurse, NA= Nurse Aide, RUG= Resource Utilization Group value, ADL= Activities of Daily Living Monthly time dummies were included in all models; output not shown.

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Table 3.3: Robustness Checks on Infection Composite

Outcome:

Infection Composite

Robustness Check 1 Robustness Check 2

Coefficient (IRR)

SE p Coefficient (IRR)

SE p

Total Nursing HPRD_lag 0.983 0.010 0.103 -- -- Percent RN_lag 1.033 0.199 0.866 -- -- Percent NA_lag 1.094 0.174 0.572 -- -- Percent Contract_lag 1.176 0.248 0.442 -- -- RN Unit Tenure_lag **0.962 0.008 0.000 -- -- LPN Unit Tenure_lag **0.980 0.007 0.006 -- -- NA Unit Tenure_lag 1.003 0.009 0.714 -- -- Total Nursing HPRD -- -- -- *0.961 0.018 0.036 Percent RN -- -- -- 0.927 0.305 0.819 Percent NA -- -- -- 0.989 0.263 0.966 Percent Contract -- -- -- 0.764 0.323 0.524 RN Unit Tenure -- -- -- **0.957 0.014 0.002 LPN Unit Tenure -- -- -- **0.957 0.012 0.001 NA Unit Tenure -- -- -- 1.004 0.015 0.757 Male 1.402 0.395 0.230 0.813 0.439 0.702 Age 0.999 0.004 0.965 1.013 0.008 0.075 Race 1.203 0.171 0.192 **0.541 0.117 0.004 RUG Score **5.832 0.651 0.000 **7.844 1.673 0.000 ADL Index **1.072 0.008 0.000 1.011 0.013 0.419 Percent Short Stay **3.003 0.132 0.000 **3.504 0.319 0.000 Admissions **0.994 0.001 0.000 **0.993 0.002 0.002 Percent Dementia 1.065 0.109 0.532 **1.663 0.296 0.004 Percent Turn **1.256 0.087 0.001 -- -- -- Percent Vent *32.720 45.941 0.013 29.795 60.15 0.093

Notes. IRR= Coefficients are Incident Rate Ratios; SE= Standard errors; p= p values

* Significant at p<0.05 **Significant at p<0.01 Robustness Check1= Regression model for Infection Composite using nurse workforce variables from one month

prior (t-1); N= 10,353 Robustness Check 2= Regression model with pneumonia pulled forward in time (i.e., between minimum data set

assessments); N= 10,570 Differences in N are due to having an unbalanced panel data and missing values for pneumonia. Infection Composite= urinary tract infections, pneumonia, and pressure ulcers, _lag= Workforce variables lagged by one month, HPRD= Hours per resident day, RN= Registered Nurse, NA= Nurse Aide, RUG= Resource Utilization Group value, ADL= Activities of Daily Living; Monthly time dummies were included in all models; output not shown.

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Chapter 4: Economic Analysis

This chapter presents findings from an economic evaluation examining high versus low

levels of nurse tenure in VA CLCs. The basis for this analysis was guided from findings in

Chapter 3 in which I found that higher RN tenure was associated with decreased resident adverse

events. This paper will be submitted to Nursing Economics.

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Abstract

To better understand the tradeoffs in nursing home (NH) nurse tenure and quality of care,

this study builds on previous and ongoing research with the objective to evaluate the cost-

effectiveness of 2 nurse workforce scenarios focusing on registered nurse (RN) tenure (high

versus low), the conditional probabilities of resident transfers from NH to the hospital and

associated costs. Guided by the Consolidated Health Economic Evaluation Reporting Standards

(CHEERS) statement, the analysis was carried out from a single healthcare payer perspective

(i.e., Veterans Administration) and uses a one-month time horizon. A decision tree was

developed to model 3 different outcomes plausible in NHs. Endpoints examined were 1) dollars

per hospitalization avoided, 2) dollars per hospitalization and death avoided, and 3) dollars per

life saved. One-way sensitivity analyses were carried out by varying uncertain baseline

parameters. Results consistently showed that high RN tenure saved costs. By creating working

environments that retain RNs and result in high tenure, NH administrators and policymakers can

improve resident care quality while realizing cost savings.

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Introduction

Hospitalizations of nursing home (NH) residents are known to be frequent, costly, and

potentially avoidable (Grabowski et al., 2007; Grabowski, Stewart, Broderick, & Coots, 2008;

Ouslander et al., 2010). While hospitalizations can be medically necessary, it has been estimated

that 40% of hospital admissions could have been avoided with high quality NH care (Saliba et

al.). There are approximately 1.6 million residents in the nation’s NHs; in 2006, almost a quarter

of those admitted to a NH were transferred back to the hospital within 30 days and cost the

Medicare program $4.34 billion (Mor, Intrator, Feng, & Grabowski, 2010; O'Malley et al.,

2011). Such transitions are disruptive and disorienting for frail elders and can significantly lower

resident quality of life (Tena-Nelson et al., 2012). Furthermore, NH transfers often expose

residents to increased risks associated with hospitalizations such as medication errors and

healthcare-associated infections (Boockvar et al., 2005; Boockvar et al., 2009). Therefore,

reducing avoidable hospitalizations in NH residents has become an important clinical and policy

issue (French, Campbell, & Rubenstein, 2008) and provides an opportunity to improve

healthcare delivery and cut unnecessary healthcare expenditures (Ouslander et al., 2010). While

researchers have emphasized how some of the cost savings could be invested to improve NH

infrastructure (Grabowski et al., 2008; Horn, 2008) , it is still unclear how these savings could be

realized by retaining a skilled nurse workforce.

Currently, resident care in NHs is provided almost entirely by or under the direction of

nurses (Harrington, 2005a). Researchers have pointed to RNs’ professional knowledge and

clinical expertise as drivers for improving quality of NH care (Castle & Anderson, 2011).

Background

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Adequate nurse staffing levels and a workforce characterized by lower turnover and

higher retention have generally been concluded to provide better outcomes (Collier &

Harrington, 2008). High RN turnover in NHs has been found to be associated with poor quality

of care such as increased infection and hospitalization rates (Zimmerman et al., 2002); while

several researchers have examined facility level factors and its relationship to nurse turnover

rates, less attention has been paid to RN retention rates or tenure (i.e., number of years the RN

has stayed with an institution) and the impact on NH resident outcomes and resulting costs

(Donoghue, 2010). Castle and Engberg (Castle & Engberg, 2008) found that RNs with 5 or more

years of experience at a single facility was associated with decreased restraint use, resident pain,

pressure ulcers and indwelling catheter use. More recently, Thomas and colleagues (2013) found

that NHs with higher retention rates for licensed nurses (RN and Licensed Practical Nurses

[LPN]) was associated with a lower 30-day hospital readmission rate (beta = -0.02, p = 0.04).

Additionally, they found that higher licensed nurse retention the year prior was also associated

with a decreased readmission rate (beta = -0.02, p = 0.02). While these findings were based on a

single state and the investigators were unable to distinguish differences between RN and LPN

retention, it nevertheless has underscored the importance of targeting nurse retention in NHs.

This previous work examining NH staffing-outcome relationships primarily examined

nurse workforce attributes and resident outcomes without considering the costs of care. Or if

staffing costs were examined, they were limited to the quantity (e.g., adequate staffing hours)

(Dorr et al., 2005; Ganz et al., 2005) and not necessarily the quality (e.g., stability) of the nurse

workforce. When patient care costs in NHs and hospitals were estimated, the data came from

secondary sources or were based on plausible assumptions (Ganz et al., 2005).

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Both retention and turnover are concepts that characterize instability of the workforce.

Retention is inversely complementary to turnover (Jones, 2004). Both retention and turnover are

associated with the quality of care and have cost implications related to staff hiring and training

(Jones, 2005, 2008). Researchers have reported challenges related to capturing true turnover

costs primarily due to differences in cost classifications and lack of reliable data (Jones & Gates,

2007). In a systematic review of the literature, despite wide variation in estimates ($22,000 to

more than $64,000), the cost of turnover per RN in hospital settings was found to be high,

indicating the importance of workforce stability (Hayes et al., 2012); however, it is yet unclear

what the net costs associated with retention versus turnover are in NHs where resources are

substantially limited.

The challenge of improving resident quality of care will undoubtedly grow severe as the

nation’s population continues to grow older. While NH services may be used at any age, the need

increases dramatically with age and the most rapidly growing segment of the U.S. population is

composed of individuals aged 85 and older ("Older Americans 2010 Key Indicators of Well-

Being," 2010); in 2009, this group represented 14.3 percent of the nation’s NH population

(Agency on Aging, 2010).

The projected growth of the aging population is even more severe for the nation’s

veterans (GAO, 2005). The demand for NH services in the Veterans Administration (VA) is also

likely to increase since the proportion of veterans age 85 and over has grown from 33 percent in

2000 to 66 percent in 2010 (GAO, 2006; "Older Americans 2010 Key Indicators of Well-Being,"

2010). With the growing number of older adults anticipated to receive care in VA Community

Living Centers (CLCs), formerly known as VA NHs, it is important for VA administrators and

policymakers to understand cost-effective ways to reduce costs while still improving quality.

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And, these administrators may be willing to invest in a nurse retention program if there are clear

benefits that accrue (e.g., improved quality and lowered long term costs) even if the initial

investment cost more (Jones & Gates, 2007). However, no researchers have quantified the

economic implications of high versus low RN tenure on resident outcomes in NHs.

Objective

To better understand the tradeoffs in NH nurse tenure and quality of care, this study

builds on previous and ongoing research to evaluate the cost-effectiveness of two nurse

workforce scenarios focusing on RN tenure (high versus low), the associated conditional

probabilities of transfers from NH to the hospital and the resulting costs.

Methods

This study was guided by the Consolidated Health Economic Evaluation Reporting

Standards (CHEERS) statement (Husereau et al., 2013). CHEERS is a 24-item checklist that

ensures a standard method for transparent and complete reporting of health economic studies; it

was recently published in March 2013 and is increasingly being adopted for journal submissions

reporting economic evaluations. Table 4.1 describes the checklist items and provides an outline

of how this report meets each item.

A cost-effectiveness analysis (CEA) was carried out to model the RN tenure scenarios. A

CEA is a form of economic evaluation where both the incremental costs and consequences are

examined (Drummond, Sculpher, Torrance, O'Brien, & Stoddart, 2005). In a CEA, the

incremental consequences are measured in a single common unit, such as adverse events

avoided, life years saved or quality adjusted life years saved. A key feature of CEA is how the

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effects are summarized in an incremental cost-effectiveness ratio (ICER), which is calculated as

follows:

ICER = (C1 – C2) / (E1 – E2),

where C1 equals the cost of the higher level investment (often higher hierarchy and more

expensive), C2 equals the cost of the comparator (often lower hierarchy and less expensive), E1

equals the effect of employing the higher level investment, and E2 equals the effect of the

comparator. The ICER provides information on how much the decision maker needs to spend to

realize a unit gain in effectiveness. The ICER is only calculated when one strategy is more

expensive and more effective than the comparator. Therefore, when a strategy is dominant (i.e.,

less expensive and more effective than the comparator), it is considered to be cost saving and

ICERs are not reported. Conversely, when a strategy is dominated (i.e., more expensive and less

effective than the comparator), the calculation of an ICER is not needed (Muennig, 2008).

Study Design/Time Horizon

A decision tree model was constructed to estimate the incremental cost- effectiveness of

RN tenure scenarios on NH resident transfers to the hospital and associated costs. A decision tree

is a mathematical modeling technique used to calculate the costs and effects associated with

events in an event pathway (Muennig, 2008). Figure 4.1 depicts the decision tree used for the

analysis. The decision node represented as a square indicates the decision of having a NH

staffing scenario with high versus low levels of RN tenure. Branching out from the two

alternative decisions are the chance nodes (the circles), which indicate the conditional probability

of residents getting hospitalized according to the tenure levels. The residents then either have the

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probability of returning back to the NH or dying during the hospitalization. The terminal node

(triangle) indicates the end points of the evaluation.

The decision was modeled to assess the 3 different outcomes between high and low RN

tenure levels. The three different models, each with different assumptions, were developed by

assigning different values (hence different outcomes) to the terminal nodes. The outcomes were

defined as: Model 1) dollars per hospitalization avoided, Model 2) dollars per hospitalization

and death avoided, and Model 3) dollars per life saved. The rationale for the 3 models was to

reflect the different plausible realities in NHs. For instance, Model 1 assumes death in NHs as a

“good” or positive outcome because it is under the assumption that residents may have had

advanced directives in which transfers are not appropriate and that transfers to hospitals are

inappropriate; in that case, if a hospitalization occurred, the terminal node was assigned a zero

and all other terminal nodes were assigned a one. Model 2 assumes both hospitalizations and

deaths occur as a result of poor quality care. Therefore, if either hospitalization or death

occurred, the terminal node was assigned a zero and treated as a “negative” outcome. All other

terminal nodes were assigned a one. Model 3 weights survival regardless of hospitalization as the

good outcome. Therefore, all paths in which residents died, the terminal nodes were assigned a

zero. All other terminal nodes were assigned a one. Because all 3 realities can exist in NHs, we

ran the basic decision tree mathematical model all three ways and examined the differences these

assumptions made in the results.

The time horizon of the modeling scenario was 1 month and therefore discounting was

not needed. A short time horizon was chosen because the median hospital length of stay of

residents transferred from NHs in the VA was 7 days and we were interested in acute transitions.

Furthermore, in this population some residents do not survive beyond 30 days and therefore a

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shorter time frame was chosen to model a more realistic NH transition scenario. Because of the

short time horizon, life years and quality adjusted life years were deemed inappropriate

outcomes. The decision tree was constructed in TreeAge Pro 2013 Suite (TreeAge Software,

Williamstown, MA).

Perspective:

The study was modeled from a single healthcare payer perspective. The model included

accrued costs from both NHs and hospitals within the VA setting.

Variables and Data Sources

This study builds on retrospective data collected for a larger study examining VA long-

term care nursing care quality and resident safety (RWJF #63959). An existing dataset of unit-

level resident data and nurse workforce data from fiscal years 2003-2008 (October 2002 to

September 2008) was examined. Details of the dataset have been provided elsewhere (Uchida,

Stone, Schmitt, & Phibbs, unpublished work). Institutional review board approval was obtained

from both Columbia University Medical Center and Stanford University.

The variable definitions, base case values and ranges are outlined in Table 4.2. All data

came from VA sources with the exception of RN replacement cost. The data sources and

estimation procedures are detailed for each variable.

NH hospitalization rates, NH mortality rates and RN tenure levels were based on VA NH

units with short and long-stay residents, which came from 20 out of the 21 total VA integrated

networks (VISN) across thirty-seven states. Hospital mortality rates and median hospital length

of stay were calculated from the VA internal databases and resident enrollment files. Cost

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parameters were primarily derived from the VA Health Economics Resource Center national cost

estimates for NH and hospital care. Nurse wages was assumed to increase depending on how

long one worked within an institution. However, primary data on annual wage increase by one

year of tenure was not directly available; therefore, VA wage increase was defined by “step”

increases in the salary pay grade and was used as a proxy to quantify wage differentials between

high versus low tenure levels. Monthly RN costs were calculated using the mean VA hourly

wage. Using the VA payroll data, the average “step increase” differential among RNs in 2003-

2008 was 2.5% to 3.5%. In our models, the average “step increase” was interpreted as one year

of tenure and a conservative rate of 2.7% was assumed.

To quantify the replacement cost of RNs in NHs, cost categories including pre and post

hiring were calculated based on previous findings in the literature (Caudill & Patrick, 1991;

Jones, 2008; Jones & Gates, 2007). Pre hire costs consisted of advertising for recruitment, hiring,

and vacancy costs (hiring temporary staff, overtime, productivity losses, etc.). Post hire costs

included orientation and training costs of the new RN, and new RN productivity losses.

A hospital cost per day was based on the median cost of a hospital day among residents

who were transferred to the hospital from the VA NH. A NH cost per day was based on the

median cost of a NH day for those residents who remained in the VA NH. All costs were inflated

to 2012 dollars using the Medical Consumer Price Index (Halfhill, 2013; US Department of

Labor).

Strategy-High versus Low RN Tenure

We identified the effectiveness of high and low levels of tenure by calculating the

resident hospitalization rates stratified by RN tenure levels (deciles). The top and bottom deciles

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were used as the basis for our baseline conditional probability estimates (①). In the high tenure

scenario, the average RN tenure was 6.7 years compared to the low tenure scenario, in which the

average RN tenure was 2.5 years.

Data Analysis-Base Case Analysis

Several assumptions were made to simulate the course of a NH resident’s transition. The

major assumptions are listed in Table 4.3 and summarized below.

Assumptions of Transitional Flow and Cost Calculations

First, for the purposes of the evaluation, we assumed a one month scenario for a NH unit

with 32 residents under supervision by 1 RN (CMS, 2001). We modeled four definitive

endpoints. For those residents who were hospitalized, they were either discharged back to the

VA NH or died during the hospitalization. For those residents who were not hospitalized, they

either remained in the NH or died. Given the close proximity of VA NHs to the VA Medical

Centers, it was therefore assumed that residents were discharged back to their original NH.

Probabilities for mortality following whether the resident was hospitalized or not was assumed to

be the same between the two tenure scenarios (②③).

Although we were able to retrieve estimates of the median length of stay in hospitals,

primary data on length of stay prior to dying in a hospital was not available. Therefore, it was

assumed that a resident died within 48 hours of being hospitalized. For these residents, daily

hospital costs were counted for 2 days. An additional 15 days of daily NH costs were added to

the final cost calculation because it was assumed that residents could be hospitalized anytime

during a month following a normal distribution. For instance, if the resident was hospitalized and

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died, then costs were calculated as (2 days*daily hospital cost) + (15 days* daily NH cost). The

same logic was applied to cases in which residents remained in the NH and died (15 days *daily

NH cost).

The models assumed care under 1 RN based on a NH unit size of 32 beds. Based on

minimum RN staffing hours in many of the states, it is reasonable to assume that a typical NH

RN worked for 8 hours a day 5 days a week for 4 weeks. Given the average tenure ranged 4

years in the data, we assumed an annual wage increase of 2.7% for each year of increased tenure;

the total wage increase was therefore compounded by 4 years (the rounded difference in tenure

between the high versus low) and multiplied by the monthly RN cost.

RN replacement costs were estimated from the average of 2 previously reported study

results. Using 1990 dollars, Caudill and Patrick (1991) reported over $7000 annually to replace

one RN. Inflated, this converts to $17,829 per RN in 2012 dollars. In 2008, Jones (2008)

reported annual replacement cost per RN in hospitals to be over $82,000 in 2007 dollars (which

translates to $96,969 in 2012 dollars). Because hospitals require more resources to train and fill

vacancies, we made a conservative assumption of a 50% reduction in those costs for NHs.

Assuming 2 RNs are replaced in a year, we calculated an average monthly RN replacement cost

and added this value to the RN cost of the low tenure branch.

Sensitivity Analysis

A number of key variables were subjected to a one-way sensitivity analysis. In a one-way

analysis, an input variable is allowed to vary (while holding all else constant) from the minimum

to the maximum value of its range (Muennig, 2008). The purpose of a sensitivity analysis is to

test uncertain assumptions and to assess which variable(s) is most sensitive to change. Because

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VA owned and operated NHs likely differ from typical community based NHs (in terms of its

resources and resident mix), we attempted to reflect these differences by testing our variables

across a wide range of possible values.

Results

Table 4.4 displays results of the 3 models. The total costs of care for the low tenure

scenario were $34,108 per month compared to the high tenure scenario at $29,442 per month.

Effectiveness of the high tenure was greater across all 3 models, indicating that high tenure was

the dominant strategy (that is less costly and more effective). The incremental cost difference

per month between the high and low tenure scenario was $4,655. The magnitude of this cost is

substantial when considering the potential savings to the VA healthcare system. Assuming a

median size NH unit with 32 patients, if the NH is able to create working environments that lead

to higher RN tenure, the annual net savings translates to greater than $55,000 per unit (i.e.,

4,655*12 = 55,860). With 133 VA NH facilities across the nation with 340 units, this roughly

translates to savings of over $18 million (55,860*340 = 18,992,400).

A summary of the sensitivity analyses are presented in Table 4.5. The results were

insensitive to variations in NH cost and hospital daily costs. However, across all 3 models, the

results of the base case were sensitive to changes in hospitalization rates, RN replacement costs

and RN wage increases by tenure. For instance, when RN replacement costs went below $1,000

per month, the high tenure strategy was no longer dominant. When RN step increases went

above 9.76%, high RN tenure was no longer dominant. Only Model 3 was sensitive to hospital

mortality probabilities beyond 10% and NH mortality rates less than 20%. In other words, when

hospital mortality rates are above 10% or NH mortality rates are below 20%, then high RN

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tenure strategy was dominant for reducing dollars per life saved; however, if monthly mortality

probabilities changed beyond these rates, then having higher RN tenure was no longer cost

saving.

Discussion

Higher RN tenure was a dominant strategy across the 3 models. This was a fairly robust

finding despite the variations in the model and uncertainty in the input parameters. In Model 3

where the outcome measure was dollars per life saved, the only parameters that the results were

sensitive to were the probabilities of hospital and NH mortality. In all models, the results were

sensitive to relatively high wage differentials and low replacement costs.

The findings from this analysis have implications for NH administrators and

policymakers and echo recommendations from previous researchers to focus attention on

retaining a skilled RN workforce. The idea for building a business case for RN retention is not a

new phenomenon (Horn, 2008; Jones, 2008). However, little was known about cost savings that

could be realized from retaining a skilled RN workforce in NHs; furthermore, these savings

provide additional resources that could be invested to further improve resident quality of life

such as training for RNs in the area of gerontology (Maas, Specht, Buckwalter, Gittler, &

Bechen, 2008). It is important to note that while higher RN tenure may result in higher salary

costs per RN, these costs outweigh the additional required expenditures in units staffed by RNs

with lower tenure related to recruiting and replacing the workforce.

While VA NH mortality rates were quite comparable to community NH values (3.2% in

our study and 2.5% reported in community NHs (Bronskill et al., 2009), the hospital mortality

rates in the VA were high (i.e., 25.9%). Spector and colleagues reported a 8.1% hospital

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mortality rate among residents transferred from a NH (Wier et al., 2012). This rate falls under

10% range examined in our sensitivity analysis. While direct comparisons cannot be made

between VA NHs and non-VA community NHs, differences in resident characteristics and

reasons for transferring residents have been reported (French et al., 2008; Givens, Selby,

Goldfeld, & Mitchell, 2012), which likely impact these rates. Because VA NHs are closely

located within VA Medical Centers, it could be that residents were only transferred to the

hospital under the most serious conditions.

Limitations

There are several limitations and caveats in interpreting these results. First, we were not

able to differentiate potentially avoidable or medically necessary hospitalizations. Second, this

analysis did not consider cases in which residents could be discharged to the community. Third,

patient preferences (e.g., advanced directives) and provider attitudes (e.g., overburdening of

staff), factors previously found to be associated with increased resident hospitalizations (Givens

et al., 2012; Grabowski et al., 2008) were also not considered. Not being able to differentiate

between short-stay and long-stay residents also limits our analysis because residents may have

different resource utilization profiles (French et al., 2008). Fourth, the level and content of

specialty training and leadership skills each nurse may have was not considered, which may

impact the NH hospitalization rates. For instance, a RN with recent specialty training may

potentially reduce hospitalizations regardless of the number of years with an institution. Fifth,

while we calculated NH RN costs using a wage increase of 2.7%, it is important to note that

wage increases may not be linear and it depends on local market characteristics (Rondeau,

Williams, & Wagar, 2008). Sixth, quality of life factors were not adjusted in our models;

however, given the very short time horizon it would have been inappropriate to assign a quality

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of life weight. Finally, our study has limited generalizability in that the analysis was conducted

under a single healthcare payer perspective, which is not typical of all NHs across the nation.

However, the estimates of the effects from this model may be useful in setting parameters and

for considering the potential cost savings at a national level. Unlike the private sector, where the

decision to hospitalize a resident may be influenced by financial incentives (i.e., NH care paid

for by state Medicaid programs and hospitalizations paid for by Medicare), the VA NHs do not

operate under such incentives (French et al., 2008) and therefore this distinct feature may

generate additional opportunities to benchmark cost estimates of nurse tenure on reducing

resident adverse outcomes. Furthermore, with the enactment of the 2010 Patient Protection and

Affordable Care Act (PPACA) and the Centers for Medicare and Medicaid Services (CMS) NH

Value-Based Purchasing Demonstration, efforts to reduce avoidable hospitalizations and

improve nurse workforce stability will be of increasing importance to non-VA NH settings (Mor

et al., 2010; Thomas et al., 2013).

Although a decision tree model is an appropriate way to compare the cost-effectiveness

of the two staffing scenarios, other modeling techniques may also be beneficial. In our analysis

we did not consider resident transitions as a recursive event. Compared to a decision tree where

there is a finite time horizon and transitions can only occur once, a Markov simulation model

allows residents to transition through the health states more than once and may provide a more

realistic picture of the costs and effects associated with different workforce profiles. We

recommend further modeling be conducted by differentiating short and long-stay residents, using

a longer time horizon.

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Conclusion

Aligning quality outcomes with cost effectiveness is imperative to driving the direction of

health policy in the United States. While there have been policy interest in lowering NH

hospitalizations and improving nurse retention, there has been little research documenting the

associated financial costs. This paper has attempted to quantify those costs so NH administrators

and policymakers can allocate NH resources more efficiently. Better prevention of

hospitalizations by having an experienced RN workforce will not only improve resident quality

of care but will allow NHs to realize the value of retaining a skilled workforce.

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Table 4.1: CHEERS Statement

CHEERS Checklist: Items to include when reporting economic evaluations of health interventions

Section/ Topic # Checklist Item Title Title 1 Economic Evaluation of Registered Nurse Tenure on Nursing

Home Resident Outcomes Abstract Structured summary 2 Objective: To better understand the tradeoffs in NH nurse

tenure and quality of care, this study builds on previous and ongoing research to evaluate the cost-effectiveness of two nurse workforce scenarios focusing on RN tenure (high versus low), the associated transfers from NH to the hospital and the associated costs. Perspective: Single healthcare payer perspective (VA) Setting: VA owned and operated NHs and medical centers Methods: CEA using decision tree modeling based on 3 different outcomes Results: Higher tenure is more cost effective and this was a robust finding across the analyses. Conclusions: NHs could realize cost savings in retaining an experienced RN workforce

Introduction Background 3 Little is known about the economic implications of NH RN tenure

on resident outcomes Objectives To better understand the tradeoffs in NH nurse tenure and

quality of care, this study builds on previous and ongoing research to evaluate the cost-effectiveness of two nurse workforce scenarios focusing on RN tenure (high versus low), the associated transfers from NH to the hospital and the associated costs.

Methods Target population and subgroups 4 NH residents cared for by RNs in VA NHs Setting and location 5 Setting: VA NH and VA Medical Center

Location: National Study perspective 6 Healthcare payer (NH and Hospital) Comparators 7 RN tenure levels (lowest decile vs highest decile) Time horizon 8 1 month Discount rate 9 NA; 1 month time horizon, discounting not needed. Choice of health outcomes 10

3 Outcomes: 1) $ per Hospitalization Avoided, 2) $ per Hospitalization and Death Avoided, 3) $ per Life Saved

Measurement of effectiveness 11a Single study based estimates: Hospitalization rates based on RN tenure levels estimated from VA original dataset and VA internal datasets.

11b Synthesis based estimates: Uncertainty surrounding RN replacement costs and therefore derived from NH literature

Measurement/valuation of preference based outcomes

12 No QALYs used

Estimating resources and costs 13a

Single study based estimates: Costs and probabilities calculated from VA databases

Currency, price, date, and conversion

14

U.S. dollar; all costs inflated to 2012 dollars using Medical CPI

Choice of model 15 CEA employing decision tree—2 staffing scenarios (high vs. low RN tenure)

Assumptions 16 See Table 3.

Analytical methods 17 Used TreeAge Pro Suite software to calculate costs and effectiveness. One way sensitivity analyses conducted on probabilities for hospitalization, mortality and RN replacement costs.

Results Study parameters 18 From NH to Hospitalization to NH or death Incremental costs and outcomes 19 Costs: RN wage costs by tenure level+ daily NH/hospital

cost*length of time in respective institution Characterizing uncertainty 20a Perspective is only from a single healthcare payer; VA is unique

and costs often do not translate to community NHs; VA NHs have higher overhead costs because they share costs with the

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Medical Center located in close proximity Characterizing heterogeneity 21 Univariate sensitivity analyses run across wide plausible values Discussion Study findings, limitations, generalizability, and current knowledge

22 Based on one study parameters for VA tenure. Limited generalizability, uncertainty surrounding hospitalization rates and mortality rates. Could not differentiate between medically necessary or inappropriate hospitalization

Other Sources of funding 23 This paper was supported by the National Institutes of Health,

National Institute of Nursing Research [F31NR013810] , the Robert Wood Johnson Foundation (RWJF #63959) and the Jonas Center for Nursing Excellence

Conflicts of interest 24 All authors declare no conflict of interest

Note. RN= Registered Nurse, VA= Veterans Affairs, NH= Nursing Homes

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Figure 4.1: Decision tree

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Table 4.2: Model Baseline Estimates

Variable Baseline Estimates Range

Hospitalization Rates by Tenure Levels Low tenure hospitalization rate % (Bottom 10% RN Tenure)

.044 0-0.098

High tenure hospitalization rate % (Top 10% RN Tenure)

.026 0-0.074

Mortality Probabilities Probability death in hospital given transfer from VA NH %

0.259 0.226-0.304

Probability of death in VA NH given there is no transfer %

0.032 0-0.560

Length of Stay Median hospital length of stay (days) among residents transferred from VA NH

7 5-12

Cost Parameters Median daily cost of hospitalization for VA NH residents transferred to hospital

2024.69 510.60-9376.86

Median daily cost of VA NH stay 669.88 155.00-928.45 Mean hourly wage of VA NH RN 53.46 -- RN replacement/ replacement cost 5,526.13 2971.50-8080.75 VA wage per step increase % 0.027 0.025-0.035 Note. Costs are displayed in 2012 dollars. All data come from the VA with the exception of the RN replacement cost, which is

estimated from the literature. RN= Registered Nurse, VA= Veterans Affairs, CLC= Community Living Centers, formerly known

as VA Nursing Homes

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Table 4.3: List of Major Assumptions

Model Overall Assumptions:

One month is assumed to be 30 days

Transition Assumptions:

Residents are assumed to follow 2 options: transfer to the hospital or remain in

the NH (i.e., transfer to home or other community NH is not considered).

Hospital and NH mortality are the same regardless of RN tenure levels

Residents who survive after a hospitalization go back to the original NH

Resident Transition Cost Assumptions:

NHHospitalNH= Daily hospital cost*7 days+ Daily NH cost*23 days

NHHospitalDeath= Daily hospital cost*2 days +Daily NH cost*15 days

NHNH= Daily NH cost*30 days

NHDeath= Daily NH cost*15 days

RN Cost Assumptions:

RN Cost for Low Tenure= 1 RN*40 hours/week*5days*4weeks= $8,533.60

RN Cost for High Tenure= RN Cost for Low Tenure* (1.027)^4= $9,515.48

RN Replacement/Recruitment Cost: Calculations based on taking the average

per RN turnover cost from the Caudill study and Jones study assuming 2 RNs

are replaced in 1 year= $5,526 per month. This additional cost was added to the

low RN tenure branches

Note. Costs are displayed in 2012 dollars. All data come from the VA with the exception of the RN replacement cost, which is

estimated from the literature. RN= Registered Nurse, NH= Nursing Home, VA= Veterans Affairs, VA NH= Commuity Living

Centers (CLC)

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Table 4.4: Summary of 3 Base Case Models

Outcome Measure Staffing

Scenario

Total Costs,

$

Incremental

Costs

Effectiveness:

Model 1)

Hospitalization

Avoided

High

Tenure

$29,442.36 -$4,665.74 0.974

Low

Tenure

$34,108.10 -- 0.956

Model 2)

Hospitalization

or Deaths Avoided

High

Tenure

$29,442.36 -$4,665.74 0.942

Low

Tenure

$34,108.10 -- 0.925

Model 3)

Life saved High

Tenure

$29,442.36 -$4,665.74 0.962

Low

Tenure

$34,108.10 -- 0.958

Note. $ = 2012 U.S. Dollars

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Table 4.5: Sensitivity Analyses

Variables Range of Values Point at which Low Tenure

strategy is no longer

dominated

Minimum Maximum

Hospitalization Rate (High Tenure) 0 1 0.06

Hospitalization Rate (Low Tenure) 0 1 0.04

Probability of Hospital Mortality* 0 1 0.1

Probability of NH Mortality* 0 1 0.2

Average Daily Hospital Cost 1 5,000 Dominated

Average Daily NH Cost 1 1,000 Dominated

Monthly RN

Replacement/Recruitment Cost

0 10,000 1,000

Wage Increase Differential by

Tenure

0 0.2 0.0976

Note. *Only Sensitive with Model 3: $ per Life Saved; Costs are displayed in 2012 dollars. NH= Nursing Home

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Chapter 5: Conclusion

The purpose of this chapter is to summarize and synthesize the findings of this

dissertation. The chapter begins with a synopsis of the systematic review and the limitations of

the current state of the science surrounding infection prevention interventions in NHs. Following

this summary, the effects of various nurse workforce characteristics on resident adverse events

are presented. Findings evaluating the economic implications of nurse tenure on NH resident

hospitalizations and associated costs are also discussed. The chapter concludes with future

research recommendations for NH practice and policy.

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Despite substantial spending and considerable regulatory oversight, the quality of care in

nursing homes (NHs) remains poor and largely inadequate. Today, there are many compelling

reasons for NHs to become engaged in improving quality of care. With major policy initiatives

implemented through the Patient Protection and Affordable Care Act (PPACA) and the NH

Value Based Purchasing Demonstration, studying ways to reduce potentially avoidable adverse

outcomes and improving nurse workforce stability is timely and critical to influencing NH

resident safety, quality of care, and costs.

Summary of Systematic Review

Based on the findings of the systematic review, the quality of infection prevention

interventions currently being conducted in NHs is generally weak. The purpose of the systematic

review was to critically review and synthesize current evidence and the methodological quality

of non-pharmacologic infection prevention interventions for institutionalized older adults. Of the

twenty-four articles that met inclusion criteria, the majority was randomized control trials which

focused on ways to reduce pneumonia. While the majority of the intervention studies reported

significant decreases of infection rates or risk factors related to infections, the methodological

clarity of available evidence was limited, which placed studies at potential risk of bias. Overall,

the interventions audited for this review varied considerably in terms of their content, intensity,

and duration. Other weaknesses included: 1) Variability in infection definitions and 2) Lack of

clarity in outcome measures reported. This made between-study comparisons extremely difficult.

Valid data regarding infection rates and risk reduction strategies are essential for guiding

surveillance and practice decisions.

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Therefore, implications from this systematic review are to enhance methodological

transparency and clarity of outcome measures and to use a standard set of infection definitions

when evaluating infection prevention interventions. Another recommendation is to enhance

methodological clarity in publications by using existing guidelines such as the consolidated

standards of reporting trials (CONSORT) for randomized control trials and the transparent

reporting of evaluations with nonrandomized designs (TREND). By ensuring adequate reporting

other clinicians and researchers can attempt to apply what was conducted in their own clinical

settings. To overcome the issue of inconsistency of infection definitions across studies, future

researchers are recommended to use the updated McGeer Criteria published in the fall of 2012

(Stone et al., 2012). Infections in NHs are costly and reflect poor quality of care. With increased

attention surrounding potentially avoidable infections, more high quality interventions are

needed.

Summary of Quantitative Findings

This quantitative portion of the dissertation examined the effects of various nurse

workforce characteristics on resident infection related outcomes. A secondary analysis using an

existing panel dataset of Veterans Affairs (VA) community living centers (CLCs), formerly

known as VA NHs was conducted. Nurse workforce characteristics for registered nurses (RN),

licensed practical nurses (LPN), nurse aides (NA), and contract nurses included: staffing levels,

percentage of hours worked and tenure. The outcome measure was a composite of resident

infection outcomes identified through the minimum data set (MDS) which included pneumonia,

urinary tract infections and pressure ulcers. Descriptive statistics and bivariate correlations were

examined. Monthly unit-level multivariate fixed effects regressions were conducted. The main

contributions of the analysis beyond prior studies include use of a longitudinal panel (monthly

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89

observations), observations at the nursing unit level rather than at the facility level, and a

comprehensive set of workforce characteristics obtained from payroll data using standardized

data collection.

The multivariate analysis revealed that RN unit tenure and LPN tenure were associated

with decreased resident infection outcomes. Therefore, the findings suggest that one way to

reduce the occurrence of resident infection outcomes in NHs is to target and minimize RN and

LPN turnover on the units. To the best of our knowledge, this is the first study to use unit-

specific longitudinal panel data to examine relationships between a comprehensive set of nurse

workforce characteristics and infection outcomes in VA NH settings.

These results also imply that in a NH setting, it is not necessarily the quantity of the

nurses or hours of care that matters in preventing infections, but how well the nurse with

supervision responsibilities is familiar with the residents and of the unit. Moreover, our findings

for RN and LPN unit tenure were robust, which calls for greater attention from NH

administrators and policymakers to recruit and retain an experienced RN and LPN workforce.

Quantitative Findings Informing the Economic Evaluation

The economic evaluation in Chapter 4 was guided by findings based on the quantitative

results. Quantitative findings from Chapter 3 suggested that having an experienced licensed

nurse workforce of RNs and LPNs was important. While it was possible to conduct an economic

evaluation for both RNs and LPNs, the financial implications for only RN tenure were examined

in Chapter 4. This decision was based to favor design simplicity but also because previous work

had already established the relationship between RN turnover and retention on resident adverse

outcomes and hospitalizations (Castle, 2005; Castle, Engberg, & Men, 2007; Thomas, Mor,

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Tyler, & Hyer, 2013; Zimmerman, Gruber-Baldini, Hebel, Sloane, & Magaziner, 2002).

Therefore the purpose of my evaluation was to extend the existing body of literature and quantify

the costs associated with resident hospitalizations and RN tenure.

Summary of Economic Evaluation

The purpose of the economic evaluation was to better understand the tradeoffs in NH RN

tenure and its impact on quality of care and costs. The study evaluated the cost-effectiveness of 2

nurse workforce scenarios focusing on RN tenure (high versus low), the conditional probabilities

of resident transfers from NH to the hospital and associated costs. The study was guided by the

Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement and

carried out from a single healthcare payer perspective (i.e., the VA). Data used in the analysis

came from the dataset used in Chapter 3. A decision tree was developed to model 3 different

outcomes plausible in NHs. Endpoints examined were 1) dollars per hospitalization avoided, 2)

dollars per hospitalization and death avoided, and 3) dollars per life saved. One-way sensitivity

analyses were carried out by varying uncertain baseline parameters such as hospitalization rates

by tenure, mortality rates, and nursing costs.

Results consistently showed that higher RN tenure was a dominant strategy across the 3

models and saved costs. Results were also fairly robust in the sensitivity analyses despite the

variations in the model and uncertainty in the input parameters. By creating working

environments that retain RNs that result in high tenure, NH administrators and policymakers can

improve resident care quality while realizing cost savings.

The findings from this analysis have implications for NH administrators and

policymakers and echo recommendations from previous researchers to focus attention on

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retaining a skilled RN workforce. While it may seem more costly to employ a nurse with longer

tenure (i.e., higher wage), my findings show that it ultimately leads to cost savings due to the

additional investments needed to recruit and replace the workforce in NHs with low tenure.

Strengths and Limitations

Strengths

There were many strengths of this dissertation. First, the systematic review followed an

existing publication guideline and a validated tool was used to assess individual study quality.

The studies were extensively reviewed by 2 reviewers, discussed among an interdisciplinary

team of researchers trained in geriatrics or infection control, and methodological problems

surrounding current infection prevention interventions in NHs were clearly identified.

For the quantitative analysis, the strengths included the ability to use a large, longitudinal

dataset that included a comprehensive set of nurse workforce characteristics. This helped to

overcome weaknesses mentioned in previous studies such as using a cross-sectional design and

relying on self-reported measures of nurse staffing collected annually at the facility level.

Furthermore, data were analyzed at the unit level, as opposed to the facility level.

Finally, the economic evaluation also used a publication guideline to enhance reporting

and clarity of the findings. This evaluation was the first study that attempted to quantify the

financial costs of having a higher RN tenure in NHs and its impact on resident hospitalizations.

While typical economic analyses would need to link multiple secondary databases to generate

the residents’ transition and mortality probabilities and related costs, using the VA dataset

allowed direct calculation using standardized data collected from multiple facilities that belonged

to the same umbrella organization. Furthermore, the VA does not have financial incentives that

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exist in the private sectors; this allows one to study the issue of nurse workforce on resident

hospitalizations without the confounding impact of Medicare and Medicaid payment incentives

(French, Campbell, & Rubenstein, 2008).

Limitations

This dissertation also has several limitations. First, with the systematic review, only

English-language articles published in peer-reviewed journals after 2001 were included.

However, given the dramatic changes in infection prevention and control over the past decade,

the relatively short time horizon can be justified. By including only published papers, publication

bias may exist. However, given that many of the studies reported non-significant findings, this is

unlikely. While attempts were made to be comprehensive in the search strategy, because our

selection criteria had a narrow focus, this may have resulted in missing some effective

interventions. Additionally, it is important to note that older adults can reside in settings other

than NHs. Finally, in assessing study quality, all of the individual studies were initially scored

independently and then combined to arrive at an average quality score; in retrospect, quality

assessment between the 2 reviewers should have been an ongoing process and a more systematic

approach to achieve high inter-rater reliability is recommended to enhance methodological rigor.

The quantitative results also have several limitations. First, a major limitation is that the

infection composite may not be representative of true NH quality and psychometric testing was

not performed to take into account the weighting of individual factors as done by others (Shwartz

et al. 2013). Conducting psychometric testing of the composite would have strengthened the

construct validity of the results. However, aggregating infection outcomes as done in my analysis

can be justified because they are commonly occurring adverse events and running these analyses

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separately with the different infection outcomes did not change my results. Second, it may be

premature to make the conclusion that RN and LPN tenure are associated with decreased resident

adverse events. Because data were aggregated at the unit level, there is risk of ecological fallacy

and findings need to be interpreted with caution. However, individual level data was not

accessible for this dissertation, and using a unit level dataset was stronger than using facility

aggregated data. A third weakness of this analysis was that it was not able to differentiate

between short and long stay NH residents on the units. Because short-stay residents are more

likely have post-acute care needs, resource use and outcomes of care may fundamentally differ.

Attempts were made to correct for this by controlling for the proportion of residents on the unit

who were expected to have a short-term stay.

Similar to the quantitative results, limitations of the economic analysis are related to

using a single healthcare payer perspective, and not being able to differentiate between short-stay

and long-stay residents. In addition, the analysis was unable to differentiate potentially avoidable

or medically necessary hospitalizations. The economic analysis also made several plausible

assumptions and did not consider cases in which residents could be discharged to the

community. Using a 1 month time horizon limited the analysis from not considering the utility of

the transition states. Not adjusting for quality of life factors may have limited the analysis

because costs and effectiveness were only reflective of outcomes seen by the healthcare payer

and does not take into account the resident’s perspective during the hospitalization.

A shared limitation across two of the Chapters for this dissertation is related to using data

from the VA and therefore may not be generalizable to non-VA NHs. However, because the VA

is a major component of the U.S. healthcare delivery system, understanding how to improve care

efficiently in this setting is important in itself. Furthermore, changes in the way healthcare is

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94

delivered within the VA may have major potential to influence the delivery of healthcare within

other government-sponsored programs and the private sector.

Some differences in the VA and non-VA settings have been noted in areas of nurse

workforce, and resident profiles. In general, VA nurse staffing levels and tenure levels are high

compared to the private sector and therefore marginal impact of changes in tenure could be

different in non-VA NHs. Selection bias of residents represented in VA NHs may vary

depending on the facility referral patterns to private sector facilities for long-term care.

Although differences exist between the VA and the general NH setting, there are also

many similarities (e.g., increasing elderly population, persistent problems with quality of care)

and therefore these results may inform other facilities throughout the U.S. healthcare delivery

system (National Commission of VA Nursing, 2004).

Future Directions for Research

Despite the several limitations, focusing on retaining a skilled nurse workforce to reduce

infection related adverse events and hospitalizations appear to present an opportunity to improve

the quality of care in NHs. First, conducting infection prevention intervention studies with

increased methodological clarity and quality is recommended. Understanding how these

interventions can be applied to other clinical practice settings is important to further expand the

NH infection prevention evidence.

Second, the influence of decreased resident infections should be explored in other

practice settings. While this dissertation only focused on NHs and especially those owned and

operated within the VA, further research with non-VA residents and nurses is recommended.

Furthermore, long-term care services currently provided to the elderly extend beyond

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institutionalized settings. Home healthcare is an increasingly growing segment of nursing service

utilization among older adults after hospitalization (Spector, Mutter, Owens & Limcangco,

2012). Research examining workforce characteristics, quality outcomes and following transitions

of individuals to and from these settings would be beneficial to enhance geriatric nursing

science.

Third, using other modeling techniques using a longer time horizon for the economic

evaluation is recommended. In my analysis resident transitions were not considered as a

recursive event. Compared to a decision tree where there is a finite time horizon and transitions

can only occur once, future research should consider using a Markov simulation model allows

residents to transition through the model more than once. This may provide a more realistic

picture of the costs and effects associated with different workforce profiles.

Finally, future analyses could use individual level resident data to more accurately

capture the relationship between nurse workforce characteristics and resident infections. If

individual data are used, other analytic methods such as survival analyses can be further explored

to estimate the individual resident’s time to acquiring an infection outcome or time to

hospitalization.

Summary of Practice Recommendations

Based on the findings of this dissertation, it is imperative that NHs are provided with

support and resources to retain their RN workforce to decrease unnecessary hospitalizations and

healthcare spending. By increasing the amount of time RNs stay in their jobs (i.e., increasing RN

retention), providers could reduce costs of advertising, recruiting, hiring and training new RNs.

Previous studies have found that lower staffing levels were associated with higher turnover rates

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(Castle & Engberg, 2006; Donoghue & Castle, 2007). Therefore, to prevent additional turnover,

NH administrators should maintain adequate staffing levels and consider investing their costs

savings from replacing RNs. Investing in supportive geriatric training as suggested previously

(Maas, Specht, Buckwalter, Gittler, & Bechen, 2008) may help existing nurses to feel more

supported in their current work environment and may also help increase retention.

Summary of Policy Recommendations

Financial incentives to reduce resident adverse outcomes have been implemented by

providing additional payments to NHs that achieve high performance by improving resident

outcomes (CMS, 2011). Under the NH Value Based Purchasing Demonstration, nursing staff

turnover, select resident quality indicators (i.e., pressure ulcers and catheter use), and avoidable

hospitalizations were among the measures for which NH performance was evaluated. While

more research is necessary to determine this relationship of nurse tenure, resident infections and

hospitalizations in non-VA settings, findings from this dissertation support policy initiatives to

publicly report nurse workforce stability rates (CDPH, 2012) on publicly available sources such

as Nursing Home Compare.

Conclusion

Improving the quality of care in NHs requires a multi-faceted approach. Retaining a

skilled nurse workforce is necessary; however it alone is not a sufficient condition for positively

affecting care in NHs. Because NHs have traditionally focused heavily on compliance with

regulatory standards, improving quality through better resident outcomes may not have been as

important as it is today. While many factors influence the quality of care provided to residents in

NHs, this dissertation emphasizes how a skilled nurse workforce plays a critical role in the

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structural element influencing NH care quality. Higher quality interventions to prevent infections

and reducing hospital transfers through nurse retention may be one way to enhance quality of

care in NHs and lower costs.

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References

Adachi, M., Ishihara, K., Abe, S., Okuda, K., & Ishikawa, T. (2002). Effect of professional oral

health care on the elderly living in nursing homes. Oral Surgery Oral Medicine Oral

Pathology Oral Radiology & Endodontics, 94(2), 191-195.

Agency on Aging. (2010). A Profile of Older Americans, Living Arrangements. Retrieved

September 23rd, 2011

http://www.aoa.gov/AoARoot/Aging_Statistics/Profile/2010/6.aspx

Allison, P. (2005). Fixed Effects Regression Methods for Longitudinal Data Using SAS.

Cary, NC: SAS Institute.

American Health Care Association. (2005). Act Now: For Your Tomorrow, National

Commission on Nursing Workforce for Long-Term Care.

http://www.ahcancal.org/research_data/staffing/Documents/Nursing_Workforce_Report.

pdf

American Health Care Association. (2011). The State Long-Term Health Care Sector

Characteristics, Utilization, and Government Funding: 2011 Update.

http://www.ahcancal.org/research_data/trends_statistics/Documents/ST_rpt_STStats2011

_20110906_FINAL_web.pdf

American Health Care Association (2012). 2011 AHCA Staffing Survey Report.

http://www.ahcancal.org/research_data/staffing/Documents/2011%20Staffing%20Survey

%20Report.pdf

Baldwin, N. S., Gilpin, D. F., Tunney, M. M., Kearney, M. P., Crymble, L., Cardwell, C., &

Hughes, C. M. (2010). Cluster randomised controlled trial of an infection control

education and training intervention programme focusing on meticillin-resistant

Page 109: Mayuko Uchida - Columbia University

99

Staphylococcus aureus in nursing homes for older people. The Journal of hospital

infection, (1), 36-41.

Banting, D. W., & Hill, S. A. (2001). Microwave disinfection of dentures for the treatment of

oral candidiasis. Special Care in Dentistry, 21(1), 4-8.

Barba, R. (2011). Admission of Nursing Home Residents to a Hospital Internal Medicine

Department. Journal of the American Medical Directors Association. doi:

10.1016/j.jamda.2010.12.095

Bartel, A. P., C; Beaulieu, N; Stone, P. (2011). Human Capital and Organizational Performance:

Evidence from the Healthcare Sector NBER Working Paper Series. Cambridge: National

Bureau of Economic Research.

Bartel, A.P., Beaulieu, N., Phibbs, C.S., Stone, P.S. (in press), Human Capital and Productivity

in a Team Environment; Evidence from the Healthcare Sector. American Economic

Journal.

Boockvar, K. S., Gruber-Baldini, A. L., Burton, L., Zimmerman, S., May, C., & Magaziner, J.

(2005). Outcomes of infection in nursing home residents with and without early hospital

transfer. Journal of the American Geriatrics Society, 53(4), 590-596.

Boockvar, K. S., Liu, S., Goldstein, N., Nebeker, J., Siu, A., & Fried, T. (2009). Prescribing

discrepancies likely to cause adverse drug events after patient transfer. Quality & Safety

in Health Care, 18(1), 32-36.

Bostick, J. E., Rantz, M. J., Flesner, M. K., & Riggs, C. J. (2006). Systematic review of studies

of staffing and quality in nursing homes. Journal of the American Medical Directors

Association, 7(6), 366-376.

Page 110: Mayuko Uchida - Columbia University

100

Bronskill, S. E., Rochon, P. A., Gill, S. S., Herrmann, N., Hillmer, M. P., Bell, C. M., . . . Stukel,

T. A. (2009). The relationship between variations in antipsychotic prescribing across

nursing homes and short-term mortality: quality of care implications. Medical Care,

47(9), 1000-1008.

California Department of Public Health [CDPH]. (2012). White Paper on Measuring Staffing

Retention/Turnover in Skilled Nursing Facilities.

http://www.cdph.ca.gov/programs/LnC/Documents/CAHPS-

2012StaffingRetentionandTurnover.pdf

Cameron, C.A., Trivedi, P.K. (2010). Microeconometrics Using Stata. College Station, Texas:

Stata Press.

Castle, N. G. (2005). Staff turnover and quality of care in nursing homes. Medical Care, 43(6),

616-626.

Castle, N. G. (2008). Nursing Home Caregiver Staffing Levels and Quality of Care: A Literature

Review. Journal of applied gerontology, 27(4), 375-405.

Castle, N. G. (2009). Use of agency staff in nursing homes. Research in Gerontological Nursing,

2(3), 192-201.

Castle, N. G., & Anderson, R. A. (2011). Caregiver staffing in nursing homes and their influence

on quality of care: using dynamic panel estimation methods. Medical Care, 49(6), 545-

552.

Castle, N. G., & Engberg, J. (2007). The influence of staffing characteristics on quality of care in

nursing homes. Health Services Research, 42(5), 1822-1847.

Castle, N. G., & Engberg, J. (2008). Further examination of the influence of caregiver staffing

levels on nursing home quality. Gerontologist, 48(4), 464-476.

Page 111: Mayuko Uchida - Columbia University

101

Castle, N. G., Engberg, J., & Men, A. (2007). Nursing home staff turnover: impact on nursing

home compare quality measures. Gerontologist, 47(5), 650-661.

Castle, N. G., & Ferguson, J. C. (2010). What is nursing home quality and how is it measured?

Gerontologist, 50(4), 426-442.

Castle, N. G., Wagner, L. M., Ferguson-Rome, J. C., Men, A., & Handler, S. M. (2011). Nursing

home deficiency citations for infection control. American Journal of Infection Control,

39(4), 263-269.

Castle, N. G., Wagner, L. M., Ferguson, J. C., & Handler, S. M. (2011). Nursing home

deficiency citations for safety. Journal of Aging & Social Policy, 23(1), 34-57.

Caudill, M. E., & Patrick, M. (1991). Costing nurse turnover in nursing homes. Nursing

Management, 22(11), 61-62, 64.

Clarke, S. P., & Donaldson, N. (2008). Chapter 25: Nurse Staffing and Patient Care Quality and

Safety. In R. Hughes (Ed.), Patient Safety and Quality: An Evidence-Based Handbook for

Nurses (Vol. AHRQ No. 08-0043). Rockville, MD: Agency for Healthcare Research and

Quality. Retrieved from http://www.ahrq.gov/professionals/clinicians-

providers/resources/nursing/resources/nurseshdbk/ClarkeS_S.pdf.

Centers for Medicare and Medicaid Services. (2011a). National Health Expenditure Database.

http://www.cms.gov/Research-Statistics-Data-and-Systems/Statistics-Trends-and-

Reports/NationalHealthExpendData/downloads/tables.pdf

Centers for Medicare and Medicaid Services. (2011b). Nursing Home Value-Based Purchasing

Demonstration. Retrieved November 2013 http://innovation.cms.gov/Files/x/NHP4P-

Summary.pdf

Page 112: Mayuko Uchida - Columbia University

102

Centers for Medicare and Medicaid Services. (2013a). National Health Expenditure Database.

http://www.cms.gov/Research-Statistics-Data-and-Systems/Statistics-Trends-and-

Reports/NationalHealthExpendData/Downloads/highlights.pdf

Centers for Medicare and Medicaid Services. (2013b). Nursing Home Compare. from

http://www.medicare.gov/nursinghomecompare/search.html

Collier, E., & Harrington, C. (2008). Staffing characteristics, turnover rates, and quality of

resident care in nursing facilities. Research in Gerontological Nursing, 1(3), 157-170.

Del Rio, R. A., Goldman, M., Kapella, B. K., Sulit, L., & Murray, P. K. (2006). The accuracy of

Minimum Data Set diagnoses in describing recent hospitalization at acute care facilities.

Journal of the American Medical Directors Association, 7(4), 212-218.

Department of Veterans Affairs (2005). VA Nursing Home Care Unit (NHCU) Admission

Criteria, Service Codes and Discharge Criteria. (VHA Directive 2005-061).

Washington, DC: VHA Retrieved from http://www.mcleague.com/mdp/pdf/Admission-

Discharge-Criteria.pdf.

Department of Veterans Affairs (2008). Criteria and Standards for VA Community Living

Centers. (VHA Handbook 1142.01). Washington DC: VHA Retrieved from

http://www.va.gov/vhapublications/ViewPublication.asp?pub_ID=1736.

Donabedian, A. (1966). Evaluating the Quality of Medical Care. The Milbank Memorial Fund

Quarterly, 44(3), Suppl-166-206.

Donoghue, C. (2010). Nursing Home Staff Turnover and Retention. Journal of applied

gerontology, 29(1), 89-106.

Dorr, D. A., Horn, S. D., & Smout, R. J. (2005). Cost analysis of nursing home registered nurse

staffing times. Journal of the American Geriatrics Society, 53(5), 840-845.

Page 113: Mayuko Uchida - Columbia University

103

Dosa, D. (2005). Should I hospitalize my resident with nursing home-acquired pneumonia?

Journal of the American Medical Directors Association, 6(5), 327-333.

Downs, S. H., & Black, N. (1998). The feasibility of creating a checklist for the assessment of

the methodological quality both of randomised and non-randomised studies of health care

interventions. Journal of Epidemiology & Community Health, 52(6), 377-384.

Drummond, M. F., Sculpher, M., Torrance, G. W., O'Brien, B. J., & Stoddart, G. L. (2005).

Methods for the Economic Evaluation of Health Care Programmes (3rd ed.). Oxford:

Oxford University Press.

Fendler, E. J., Ali, Y., Hammond, B. S., Lyons, M. K., Kelley, M. B., & Vowell, N. A. (2002).

The impact of alcohol hand sanitizer use on infection rates in an extended care facility.

American journal of infection control, 30(4), 226-233.

Frakt, A., Wang, M., & Pizer, S. (2004). Validating MDS Data from VA Nursing Home Care

Units: Comparing VA and Community Quality Measures (V. B. H. C. S. R.

Development, Trans.). Boston, MA.

French, D. D., Campbell, R. R., & Rubenstein, L. Z. (2008). Long-stay nursing home residents'

hospitalizations in the VHA: the potential impact of aligning financial incentives on

hospitalizations. Journal of the American Medical Directors Association, 9(7), 499-503.

French, D. D., Werner, D. C., Campbell, R. R., Powell-Cope, G. M., Nelson, A. L., Rubenstein,

L. Z., . . . Spehar, A. M. (2007). A multivariate fall risk assessment model for VHA

nursing homes using the minimum data set. Journal of the American Medical Directors

Association, 8(2), 115-122.

Page 114: Mayuko Uchida - Columbia University

104

Fry, A. M., Shay, D. K., Holman, R. C., Curns, A. T., & Anderson, L. J. (2005). Trends in

hospitalizations for pneumonia among persons aged 65 years or older in the United

States, 1988-2002. JAMA, 294(21), 2712-2719.

Ganz, D. A., Simmons, S. F., & Schnelle, J. F. (2005). Cost-effectiveness of recommended nurse

staffing levels for short-stay skilled nursing facility patients. BMC health services

research, 5, 35.

GAO. (2004). Oversight of Nursing Home Program Impeded by Data Gaps. Washington DC:

United States Government Accountability Office.

GAO. (2005). Long-Term Care Financing: Growing Demand and Cost Services are Straining

Federal and State Budgets. Washington DC: United States Government Accountability

Office.

GAO. (2006). VA Long-Term Care: Trends and Planning Challenges in Providing Nursing

Home Care to Veterans (Rep. No. GAO-06-333T). Washington DC: United States

Government Accountability Office.

GAO. (2011). VA Community Living Centers Actions Needed to Better Manage Risks to

Veterans' Quality of Life and Care. (GAO-12-11). Washington DC: United States

Government Accountability Office.

Givens, J. L., Selby, K., Goldfeld, K. S., & Mitchell, S. L. (2012). Hospital transfers of nursing

home residents with advanced dementia. Journal of the American Geriatrics Society,

60(5), 905-909.

Gornitsky, M., Paradis, I. I., Landaverde, G., Malo, A. M., & Velly, A. M. (2002). A clinical and

microbiological evaluation of denture cleansers for geriatric patients in long-term care

institutions. J Can Dent Assoc, 68(1), 39-45.

Page 115: Mayuko Uchida - Columbia University

105

Grabowski, D. C., O'Malley, A. J., & Barhydt, N. R. (2007). The costs and potential savings

associated with nursing home hospitalizations. Health Affairs, 26(6), 1753-1761.

Grabowski, D. C., Stewart, K. A., Broderick, S. M., & Coots, L. A. (2008). Predictors of nursing

home hospitalization: a review of the literature. Medical Care Research & Review, 65(1),

3-39.

Gruneir, A., & Mor, V. (2008). Nursing home safety: current issues and barriers to improvement.

Annual Review of Public Health, 29, 369-382.

Halfhill, T. (2013). Tom's Inflation Calculator. Retrieved October 24th, 2013, from

http://www.halfhill.com/inflation.html

Harrington, C. (2005). Nurse staffing in nursing homes in the United States. Journal of

Gerontological Nursing, 31(2), 18-23.

Harrington, C. (2005). Quality of care in nursing home organizations: establishing a health

services research agenda. Nursing Outlook, 53(6), 300-304.

Harrington, C. (2012). Nurse staffing and deficiencies in the largest for-profit nursing home

chains and chains owned by private equity companies. Health Services Research, 47(1),

106-128.

Harrington, C., Swan, J. H., & Carrillo, H. (2007). Nurse staffing levels and Medicaid

reimbursement rates in nursing facilities. Health Services Research, 42(3 Pt 1), 1105-

1129.

Harris, A. D., Lautenbach, E., & Perencevich, E. (2005). A systematic review of quasi-

experimental study designs in the fields of infection control and antibiotic resistance.

Clinical Infectious Diseases, 41(1), 77-82.

Page 116: Mayuko Uchida - Columbia University

106

Hayes, L. J., O'Brien-Pallas, L., Duffield, C., Shamian, J., Buchan, J., Hughes, F., . . . North, N.

(2012). Nurse turnover: a literature review - an update. International journal of nursing

studies, 49(7), 887-905.

Hickey, E. C., Young, G. J., Parker, V. A., Czarnowski, E. J., Saliba, D., & Berlowitz, D. R.

(2005). The effects of changes in nursing home staffing on pressure ulcer rates. Journal

of the American Medical Directors Association, 6(1), 50-53.

Horn, S. D. (2008). The business case for nursing in long-term care. Policy, Politics, & Nursing

Practice, 9(2), 88-93.

Horn, S. D., Buerhaus, P., Bergstrom, N., & Smout, R. J. (2005). RN staffing time and outcomes

of long-stay nursing home residents: pressure ulcers and other adverse outcomes are less

likely as RNs spend more time on direct patient care. American Journal of Nursing,

105(11), 58-70.

Husereau, D., Drummond, M., Petrou, S., Carswell, C., Moher, D., Greenberg, D., . . . Force, C.

T. (2013). Consolidated Health Economic Evaluation Reporting Standards (CHEERS)

statement. Value in health, 16(2), e1-5.

Hutt, E., Radcliff, T. A., Oman, K. S., Fink, R., Ruscin, J. M., Linnebur, S., . . . McNulty, M.

(2010). Impact of NHAP guideline implementation intervention on staff and resident

vaccination rates. J Am Med Dir Assoc, 11(5), 365-370.

Hyer, K., Thomas, K. S., Branch, L. G., Harman, J. S., Johnson, C. E., & Weech-Maldonado, R.

(2011). The influence of nurse staffing levels on quality of care in nursing homes.

Gerontologist, 51(5), 610-616.

Page 117: Mayuko Uchida - Columbia University

107

Improvement, T. P. C. f. P. (2010). Measures Development, Methodology, and Oversight

Advisory Committee: Recommendations to PCPI Work Groups on Composite Measures:

American Medical Association.

Intrator, O., Zinn, J., & Mor, V. (2004). Nursing home characteristics and potentially preventable

hospitalizations of long-stay residents. Journal of the American Geriatrics Society,

52(10), 1730-1736.

Institute of Medicine. (1986). Improving the Quality of Care in Nursing Homes. Washington

D.C. National Academies Press.

Institute of Medicine. (1999). To Err is Human Building a Safer Health System. Washington

D.C. National Academies Press.

Institute of Medicine. (2001). Improving the Quality of Long Term Care. Washington D.C.

National Academies Press.

Ishikawa, A., Yoneyama, T., Hirota, K., Miyake, Y., & Miyatake, K. (2008). Professional oral

health care reduces the number of oropharyngeal bacteria. Journal of Dental Research,

87(6), 594-598.

Jones AL, Dwyer LL, Bercovitz AR, Strahan GW. The National Nursing Home Survey: 2004

overview. National Center for Health Statistics. Vital Health Stat 13(167). 2009.

Retrieved from http://www.cdc.gov/nchs/data/series/sr_13/sr13_167.pdf.

Jones, C. B. (2004). The costs of nurse turnover: part 1: an economic perspective. Journal of

Nursing Administration, 34(12), 562-570.

Jones, C. B. (2005). The costs of nurse turnover, part 2: application of the Nursing Turnover

Cost Calculation Methodology. Journal of Nursing Administration, 35(1), 41-49.

Page 118: Mayuko Uchida - Columbia University

108

Jones, C. B. (2008). Revisiting nurse turnover costs: adjusting for inflation. Journal of Nursing

Administration, 38(1), 11-18.

Jones, C. B., & Gates, M. (2007). The Costs and Benefits of Nurse Turnover: A Business Case

for Nurse Retention. The Online Journal of Issues in Nursing, 12(3).

Kim, H., Harrington, C., & Greene, W. H. (2009). Registered nurse staffing mix and quality of

care in nursing homes: a longitudinal analysis. Gerontologist, 49(1), 81-90.

Kim, H., Kovner, C., Harrington, C., Greene, W., & Mezey, M. (2009). A panel data analysis of

the relationships of nursing home staffing levels and standards to regulatory deficiencies.

Journals of Gerontology Series B-Psychological Sciences & Social Sciences, 64(2), 269-

278.

Konetzka, R. T. (2008). The staffing-outcomes relationship in nursing homes. Health Services

Research, 43(3), 1025-1042.

Konetzka, R. T., Stearns, S. C., & Park, J. (2008). The staffing-outcomes relationship in nursing

homes. Health Services Research, 43(3), 1025-1042.

Konetzka, R. T., Yi, D., Norton, E. C., & Kilpatrick, K. E. (2004). Effects of Medicare payment

changes on nursing home staffing and deficiencies. Health Services Research, 39(3), 463-

488.

Kullberg, E., Sjogren, P., Forsell, M., Hoogstraate, J., Herbst, B., & Johansson, O. (2010). Dental

hygiene education for nursing staff in a nursing home for older people. J Adv Nurs, 66(6),

1273-1279.

Larson, E. L., & Cortazal, M. (2012). Publication guidelines need widespread adoption. Journal

of Clinical Epidemiology, 65(3), 239-246.

Page 119: Mayuko Uchida - Columbia University

109

Liberati, A., Altman, D. G., Tetzlaff, J., Mulrow, C., Gotzsche, P. C., Ioannidis, J. P. A., . . .

Moher, D. (2009). The PRISMA statement for reporting systematic reviews and meta-

analyses of studies that evaluate healthcare interventions: explanation and elaboration.

BMJ, 339, b2700.

Liu, B. A., McGeer, A., McArthur, M. A., Simor, A. E., Aghdassi, E., Davis, L., & Allard, J. P.

(2007). Effect of multivitamin and mineral supplementation on episodes of infection in

nursing home residents: a randomized, placebo-controlled study.[Erratum appears in J

Am Geriatr Soc. 2007 Mar;55(3):478]. Journal of the American Geriatrics Society, 55(1),

35-42.

Maas, M. L., Specht, J. P., Buckwalter, K. C., Gittler, J., & Bechen, K. (2008). Nursing home

staffing and training recommendations for promoting older adults' quality of care and

life: Part 2. Increasing nurse staffing and training. Research in Gerontological Nursing,

1(2), 134-152.

Maruyama, T., Taguchi, O., Niederman, M. S., Morser, J., Kobayashi, H., Kobayashi, T., . . .

Gabazza, E. C. (2010). Efficacy of 23-valent pneumococcal vaccine in preventing

pneumonia and improving survival in nursing home residents: double blind, randomised

and placebo controlled trial. BMJ, 340, c1004.

McElhaney, J. E., Gravenstein, S., Cole, S. K., Davidson, E., O'Neill, D., Petitjean, S., . . . Shan,

J. J. (2004). A placebo-controlled trial of a proprietary extract of North American ginseng

(CVT-E002) to prevent acute respiratory illness in institutionalized older adults. J Am

Geriatr Soc, 52(1), 13-19.

Page 120: Mayuko Uchida - Columbia University

110

McGeer, A., Campbell, B., Emori, T. G., Hierholzer, W. J., Jackson, M. M., Nicolle, L. E., . . . et

al. (1991). Definitions of infection for surveillance in long-term care facilities. American

Journal of Infection Control, 19(1), 1-7.

Meurman, J. H., Parnanen, P., Kari, K., & Samaranayake, L. (2009). Effect of amine fluoride-

stannous fluoride preparations on oral yeasts in the elderly: a randomised placebo-

controlled trial. Gerodontology, 26(3), 202-209.

Meydani, S. N., Leka, L. S., Fine, B. C., Dallal, G. E., Keusch, G. T., Singh, M. F., & Hamer, D.

H. (2004). Vitamin E and respiratory tract infections in elderly nursing home residents: a

randomized controlled trial. JAMA : the journal of the American Medical Association,

(7), 828-836.

http://www.mrw.interscience.wiley.com/cochrane/clcentral/articles/624/CN-

00480624/frame.html

Mody, L., Bradley, S. F., Galecki, A., Olmsted, R. N., Fitzgerald, J. T., Kauffman, C. A., . . .

Krein, S. L. (2011). Conceptual model for reducing infections and antimicrobial

resistance in skilled nursing facilities: focusing on residents with indwelling devices.

Clinical Infectious Diseases, 52(5), 654-661.

Mody, L., Kauffman, C. A., McNeil, S. A., Galecki, A. T., & Bradley, S. F. (2003). Mupirocin-

based decolonization of Staphylococcus aureus carriers in residents of 2 long-term care

facilities: a randomized, double-blind, placebo-controlled trial. Clinical Infectious

Diseases, 37(11), 1467-1474.

Mody, L., McNeil, S. A., Sun, R., Bradley, S. E., & Kauffman, C. A. (2003). Introduction of a

waterless alcohol-based hand rub in a long-term-care facility. Infection Control &

Hospital Epidemiology, 24(3), 165-171.

Page 121: Mayuko Uchida - Columbia University

111

Mor, V., Intrator, O., Feng, Z., & Grabowski, D. C. (2010). The revolving door of

rehospitalization from skilled nursing facilities. Health Affairs, 29(1), 57-64.

Morris, J., Moore, T., Jones, R., Mor, V., Angelelli, J., Berg, K., . . . Rennison, M. (2003).

Validation of Long-Term and Post-Acute Care Quality Indicators. Baltimore, MD.

Muennig, P. (2008). Cost-Effectiveness Analysis in Health: A Practical Approach (2nd ed.). San

Francisco, CA: Jossey-Bass.

Mukamel, D. B., Weimer, D. L., Spector, W. D., Ladd, H., & Zinn, J. S. (2008). Publication of

quality report cards and trends in reported quality measures in nursing homes. Health

Services Research, 43(4), 1244-1262.

National Commission of VA Nursing. (2004). Caring for America's Veterans: Attracting and

Retaining a Quality VHA Nursing Workforce.

National Institute of Nursing Research. Developing Knowledge for Practice: Challenges and

Opportunities, National Nursing Research Agenda from NINR, NIH, US Dept, HHS, US

Public Health Service

http://www.ninr.nih.gov/NewsAndInformation/NINRPublications/Long-

TermCareforOlderAdults.htm

Nishiyama, Y., Inaba, E., Uematsu, H., & Senpuku, H. (2010). Effects of mucosal care on oral

pathogens in professional oral hygiene to the elderly. Archives of gerontology and

geriatrics, (3), e139-143.

O'Malley, A. J., Caudry, D. J., & Grabowski, D. C. (2011). Predictors of nursing home residents'

time to hospitalization. Health Services Research, 46(1 Pt 1), 82-104.

Older Americans 2010 Key Indicators of Well-Being. (2010). Retrieved October 1st, 2011, from

Federal Interagency Forum on Aging-Related Statistics

Page 122: Mayuko Uchida - Columbia University

112

http://www.agingstats.gov/agingstatsdotnet/Main_Site/Data/2010_Documents/Docs/OA_

2010.pdf

Ouslander, J. G., Diaz, S., Hain, D., & Tappen, R. (2011). Frequency and Diagnoses Associated

With 7- and 30-Day Readmission of Skilled Nursing Facility Patients to a Nonteaching

Community Hospital. Journal of the American Medical Directors Association, 12(3),

195-203.

Ouslander, J. G., Lamb, G., Perloe, M., Givens, J. H., Kluge, L., Rutland, T., . . . Saliba, D.

(2010). Potentially avoidable hospitalizations of nursing home residents: frequency,

causes, and costs: [see editorial comments by Drs. Jean F. Wyman and William R.

Hazzard, pp 760-761]. Journal of the American Geriatrics Society, 58(4), 627-635.

Quagliarello, V., Juthani-Mehta, M., Ginter, S., Towle, V., Allore, H., & Tinetti, M. (2009). Pilot

testing of intervention protocols to prevent pneumonia in nursing home residents. Journal

of the American Geriatrics Society, 57(7), 1226-1231.

Rahman, A. N., & Applebaum, R. A. (2009). The nursing home Minimum Data Set assessment

instrument: manifest functions and unintended consequences--past, present, and future.

Gerontologist, 49(6), 727-735.

Rantz, M. J., & Connolly, R. P. (2004). Measuring nursing care quality and using large data sets

in nonacute care settings: state of the science. Nursing Outlook, 52(1), 23-37.

Richards, C. (2002). Infections in residents of long-term care facilities: an agenda for research.

Report of an expert panel. Journal of the American Geriatrics Society, 50(3), 570-576.

Richards, C. L., Jr. (2007). Infection control in long-term care facilities. Journal of the American

Medical Directors Association, 8(3 Suppl), S18-25.

Page 123: Mayuko Uchida - Columbia University

113

Rogers, M. A. M. (2008). Incidence of antibiotic-resistant infection in long-term residents of

skilled nursing facilities. American journal of infection control, 36(7), 472-475.

Rondeau, K. V., Williams, E. S., & Wagar, T. H. (2008). Turnover and vacancy rates for

registered nurses: do local labor market factors matter? Health Care Management

Review, 33(1), 69-78.

Rosen, A. K., Loveland, S., Shin, M., Shwartz, M., Hanchate, A., Chen, Q., . . . Borzecki, A.

(2013). Examining the impact of the AHRQ Patient Safety Indicators (PSIs) on the

Veterans Health Administration: the case of readmissions. Medical Care, 51(1), 37-44.

Saliba, D., Kington, R., Buchanan, J., Bell, R., Wang, M., Lee, M., . . . Rubenstein, L.

Appropriateness of the decision to transfer nursing facility residents to the hospital.

Journal of the American Geriatrics Society, 48(2), 154-163.

Samoocha, D., Bruinvels, D. J., Elbers, N. A., Anema, J. R., & van der Beek, A. J. (2010).

Effectiveness of web-based interventions on patient empowerment: a systematic review

and meta-analysis. Journal of Medical Internet Research, 12(2), e23.

Sangl, J., Saliba, D., Gifford, D. R., & Hittle, D. F. (2005). Challenges in measuring nursing

home and home health quality: lessons from the First National Healthcare Quality

Report. Medical Care, 43(3 Suppl), I24-32.

Schnelle, J. F., Simmons, S. F., Harrington, C., Cadogan, M., Garcia, E., & B, M. B.-J. (2004).

Relationship of nursing home staffing to quality of care. Health Services Research, 39(2),

225-250.

Centers for Medicare and Medicaid Services. (2001). Report to Congress: Appropriateness of

Minimum Nurse Staffing Ratios in Nursing Homes (Vol. Phase II Final, Volumes I-III).

Baltimore, MD.

Page 124: Mayuko Uchida - Columbia University

114

Setodji, C. M., & Shwartz, M. (2013). Fixed-effect or random-effect models: what are the key

inference issues? Medical Care, 51(1), 25-27. doi:

http://dx.doi.org/10.1097/MLR.0b013e31827a8bb0

Siegel, J. E., & Clancy, C. M. (2006). Relative value in healthcare: cost-effectiveness of

interventions. Journal of Nursing Care Quality, 21(2), 99-103.

Sjogren, P., Nilsson, E., Forsell, M., Johansson, O., & Hoogstraate, J. (2008). A systematic

review of the preventive effect of oral hygiene on pneumonia and respiratory tract

infection in elderly people in hospitals and nursing homes: effect estimates and

methodological quality of randomized controlled trials. Journal of the American

Geriatrics Society, 56(11), 2124-2130.

Smith, P. W., Bennett, G., Bradley, S., Drinka, P., Lautenbach, E., Marx, J., . . . Apic. (2008).

SHEA/APIC guideline: infection prevention and control in the long-term care facility,

July 2008. Infection Control & Hospital Epidemiology, 29(9), 785-814.

Spector, W., Mutter, R., Owens, P., & Limcangco, R. (September 2012). Transitions between

Nursing Homes and Hospitals in the Elderly Population, 2009 HCUP Statistical Brief

#141. Rockville, MD: Agency for Healthcare Research and Quality. http://www.hcup-

us.ahrq.gov/reports/statbriefs/sb141.pdf

Spector, W. D., & Takada, H. A. (1991). Characteristics of nursing homes that affect resident

outcomes. Journal of Aging & Health, 3(4), 427-454.

Stone, N. D., Ashraf, M. S., Calder, J., Crnich, C. J., Crossley, K., Drinka, P. J., . . . Society for

Healthcare Epidemiology Long-Term Care Special Interest, G. (2012). Surveillance

definitions of infections in long-term care facilities: revisiting the McGeer criteria.

Infection Control & Hospital Epidemiology, 33(10), 965-977.

Page 125: Mayuko Uchida - Columbia University

115

Strausbaugh, L. J., & Joseph, C. L. (2000). The burden of infection in long-term care. Infection

Control & Hospital Epidemiology, 21(10), 674-679.

Tena-Nelson, R., Santos, K., Weingast, E., Amrhein, S., Ouslander, J., & Boockvar, K. (2012).

Reducing potentially preventable hospital transfers: results from a thirty nursing home

collaborative. Journal of the American Medical Directors Association, 13(7), 651-656.

Teresi, J. A., Holmes, D., Bloom, H. G., Monaco, C., & Rosen, S. (1991). Factors differentiating

hospital transfers from long-term care facilities with high and low transfer rates.

Gerontologist, 31(6), 795-806.

Thai, T. P., Keast, D. H., Campbell, K. E., Woodbury, M. G., & Houghton, P. E. (2005). Effect

of ultraviolet light C on bacterial colonization in chronic wounds. Ostomy Wound

Manage, 51(10), 32-45.

Thomas, K. S., Mor, V., Tyler, D. A., & Hyer, K. (2013). The relationships among licensed

nurse turnover, retention, and rehospitalization of nursing home residents. Gerontologist,

53(2), 211-221.

Trick, W. E., Weinstein, R. A., DeMarais, P. L., Tomaska, W., Nathan, C., McAllister, S. K., . . .

Jarvis, W. R. (2004). Comparison of routine glove use and contact-isolation precautions

to prevent transmission of multidrug-resistant bacteria in a long-term care facility

(Provisional abstract). Journal of the American Geriatrics Society, (12), 2003-2009.

U.S. Department of Health and Human Services, D. (2009). National Action Plan to Prevent

Healthcare Associated Infections: Road Map to Elimination Part 3: Phase One-Acute

Care Hospitals.

Page 126: Mayuko Uchida - Columbia University

116

U.S. Department of Health and Human Services, D. (2013). National Action Plan to Prevent

Health Care-Associated Infections: Road Map to Elimination. Washington D.C.:

Retrieved from http://www.hhs.gov/ash/initiatives/hai/actionplan/hai-action-plan-ltcf.pdf.

Uchida, M., Pogorzelska-Maziarz, M., Smith, P. W., & Larson, E. (2013). Infection prevention

in long-term care: a systematic review of randomized and nonrandomized trials. Journal

of the American Geriatrics Society, 61(4), 602-614.

Uchida, M., Stone, P., Schmitt, S., & Phibbs, C. (unpublished work). Nurse Workforce

Characteristics and Quality of Care in Department of Veterans Affairs Community Living

Centers: A Longitudinal Analysis.

US Department of Labor, Bureau of Labor Statistics. Measuring price change for medical care

in the CPI. http://www.bls.gov/cpi/cpifact4.htm

Wan, T. T., Zhang, N. J., & Unruh, L. (2006). Predictors of resident outcome improvement in

nursing homes. Western journal of nursing research, 28(8), 974-993.

Washington, E. A. (2001). Instillation of 3% hydrogen peroxide or distilled vinegar in urethral

catheter drainage bag to decrease catheter-associated bacteriuria. Biol Res Nurs, 3(2), 78-

87.

Watando, A., Ebihara, S., Ebihara, T., Okazaki, T., Takahashi, H., Asada, M., & Sasaki, H.

(2004). Daily oral care and cough reflex sensitivity in elderly nursing home patients.

Chest, 126(4), 1066-1070.

Weech-Maldonado, R., Meret-Hanke, L., Neff, M. C., & Mor, V. (2004). Nurse staffing patterns

and quality of care in nursing homes. Health Care Management Review, 29(2), 107-116.

Weinstein, M., & Skinner, J. (2010). Comparative Effectiveness and Health Care Spending

Implications for Reform. New England Journal of Medicine, 362(5), 460-465.

Page 127: Mayuko Uchida - Columbia University

117

Wendt, C., Schinke, S., Württemberger, M., Oberdorfer, K., Bock-Hensley, O., & von Baum, H.

(2007). Value of whole-body washing with chlorhexidine for the eradication of

methicillin-resistant Staphylococcus aureus: a randomized, placebo-controlled, double-

blind clinical trial. Infection control and hospital epidemiology, (9), 1036-1043.

Werner, R. M., & Konetzka, R. T. (2010). Advancing nursing home quality through quality

improvement itself. Health Affairs, 29(1), 81-86.

Wier, L. M. P., A.; Steiner, C. (2010). Hospital Utilization among Oldest Adults, 2008. In U. S.

A. f. H. R. a. Quality (Ed.), HCUP Statistical Brief #103. Rockville, MD.

http://www.hcup-us.ahrq.gov/reports/statbriefs/sb103.pdf

Yamada, H., Takuma, N., Daimon, T., & Hara, Y. (2006). Gargling with tea catechin extracts for

the prevention of influenza infection in elderly nursing home residents: a prospective

clinical study. Journal of alternative and complementary medicine (New York, N.Y.), (7),

669-672.

Yoneyama, T., Yoshida, M., Ohrui, T., Mukaiyama, H., Okamoto, H., Hoshiba, K., . . . Oral

Care Working, G. (2002). Oral care reduces pneumonia in older patients in nursing

homes. Journal of the American Geriatrics Society, 50(3), 430-433.

Zimmerman, S., Gruber-Baldini, A. L., Hebel, J. R., Sloane, P. D., & Magaziner, J. (2002).

Nursing home facility risk factors for infection and hospitalization: importance of

registered nurse turnover, administration, and social factors. Journal of the American

Geriatrics Society, (12), 1987-1995.

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List of Appendices

Appendix A, Chapter 1

MDS 2.0 Resident Assessment Form

Appendix B, C, Chapter 2

PRISMA Checklist

Quality Assessment Tool

Appendix D, E, F, Chapter 3

Detailed Summary of Monthly Unit Level Nurse Workforce Characteristics

Correlation Matrix of Independent Variables

Effects of Staffing on Composite under Different Model Assumptions

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Appendix A. MDS 2.0 Resident Assessment Form

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Appendix B. PRISMA Checklist PRISMA Checklist of Intervention Studies Section/ Topic # Checklist Item Title Title 1 Infection Prevention in Long-Term Care: A Systematic

Review of Randomized and Non-Randomized Trials Abstract Structured summary 2 Background: Little is known about infection prevention

interventions in long-term care (LTC). Objective: To critically review and synthesize current

evidence and the methodological quality of infection prevention interventions in LTC. Methods: Two reviewers systematically searched 3

electronic databases MEDLINE, PUBMED, and Cochrane Controlled Trials Register for studies published over the last decade assessing randomized and non-randomized trials with older adults in which primary outcomes were infection rates and reductions of risk factors related to infections. To establish clarity and standardized reporting of findings, the PRISMA (preferred reporting items for systematic reviews and meta-analyses) checklist was used. Data Analysis: Data were extracted based on study

design, sample size, type and duration of interventions, outcome measures reported, and findings. Study quality was assessed by two reviewers using a validated standardized quality assessment tool. Inter-rater reliability was found to be excellent. Results: 24 articles met inclusion criteria. The majority

were randomized control trials (67%), where the primary interest was to reduce pneumonia (63%) and focused on therapeutic interventions (71%). Thirteen (54%) of 24 studies reported statistically significant results in favor of interventions on at least one of their outcome measures. The interventions audited for this review varied considerably in terms of their nature, intensity, and duration. The methodological clarity of available evidence was limited, placing them at potential risk of bias. Conclusions/ Implications: Gaps and inconsistencies

surrounding interventions in LTC are evident. Future interventional studies need to enhance methodological clarity using clearly defined outcome measures and standardized reporting of findings.

Introduction Rationale 3 Little is known about infection prevention interventions

conducted in long-term care facilities (LTCF); this systematic review aims to clarify the state of the science surrounding infection prevention interventions in LTC.

Objectives 4 To identify intervention studies (RCTs and non-RCTs) assessing the effects of infection prevention measures conducted in LTC with elderly in which primary outcomes are infection rates and reductions of risk factors shown to be related to infections.

Methods Protocol and registration 5 Methods of the analysis and inclusion criteria were

specified in advance and documented; no registration # Eligibility criteria 6 Population: Seniors ≥60 residing in LTC facilities;

Intervention: Studies conducted in LTC facilities aiming

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to reduce infections; Outcome: infection rates and

reductions of risk factors shown to be related to infections. Excluded were interventions in which outcomes focused only on healthcare workers and systemic pharmacological interventions other than vaccines. Interventions that only evaluated the efficacy or immunogenicity of vaccines were also excluded.

Information sources 7 Intervention studies published in English from January 2001 through June 2011;

Search 8 1. exp Long-Term Care/

2. exp Nursing Homes/

3. exp Skilled Nursing Facilities/

4. exp Infection/

5. 1 and 2 and 3 and 4

6. exp Pneumonia/

7. exp Sepsis/

8. exp Urinary Tract Infections/

9. blood stream infections.mp.

10. exp Bacteremia/

11. multiple drug resistant organisms.mp.

12. exp Infection Control/

13. 1 or 2 or 3

14. 6 and 13

15. 7 and 13

16. 8 and 13

17. 10 and 13

18. 12 and 13

19. limit 14 to (english language and humans and last 10

years)

20. limit 19 to (english language and ("all aged (65 and

over)" or "aged (80 and over)") and english and humans

and (comparative study or controlled clinical trial or

guideline or journal article or meta analysis or practice

guideline) and last 10 years)

21. limit 15 to (english language and humans and ("all

aged (65 and over)" or "aged (80 and over)") and english

and humans and (comparative study or controlled

clinical trial or evaluation studies or guideline or

journal article or practice guideline or randomized

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controlled trial) and last 10 years)

22. limit 16 to (english language and humans and ("all

aged (65 and over)" or "aged (80 and over)") and english

and humans and (comparative study or controlled

clinical trial or evaluation studies or guideline or

journal article or practice guideline or randomized

controlled trial) and last 10 years)

23. limit 17 to (english language and humans and ("all

aged (65 and over)" or "aged (80 and over)") and english

and humans and (comparative study or controlled

clinical trial or evaluation studies or guideline or

journal article or practice guideline or randomized

controlled trial) and last 10 years)

24. limit 18 to (english language and humans and ("all

aged (65 and over)" or "aged (80 and over)") and english

and humans and (comparative study or controlled

clinical trial or evaluation studies or guideline or

journal article or practice guideline or randomized

controlled trial) and last 10 years)

25. exp Clostridium difficile/

26. 13 and 25

27. limit 26 to (english language and humans and ("all

aged (65 and over)" or "aged (80 and over)") and english

and humans and (comparative study or controlled

clinical trial or evaluation studies or guideline or

journal article or practice guideline or randomized

controlled trial) and last 10 years)

28. exp Drug Resistance, Microbial/ or exp Drug

Resistance, Bacterial/

29. 13 and 28

30. limit 29 to (english language and humans and ("all

aged (65 and over)" or "aged (80 and over)") and english

and humans and (comparative study or controlled

clinical trial or evaluation studies or guideline or

journal article or practice guideline or randomized

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controlled trial) and last 10 years)

Study selection 9 Two review authors (MU, MP) independently reviewed the abstracts using the following inclusion criteria: 1. Older adults 65 years or older; 2. Long-term care facilities (i.e., nursing homes, skilled nursing facilities) or long-term care centers not part of the hospital building; 3. Infection rates; 4. Intervention studies. Disagreements were resolved by third and fourth review authors (PWS and ELL).

Data collection process 10 Two reviewers (MU and MP) assessed study eligibility. First, MU independently screened abstract titles for which MP reviewed and confirmed eligibility.

Data items 11

Data were extracted based on objectives, study design, sample size, type and duration of interventions, outcome measures reported, and findings. Also abstracted data by country, the number of interventions employed, the number of sites tested in a given study and whether or not the residents played a direct participatory role during the interventions.

Risk of bias in individual studies

12 See narrative Allocation concealment, selection bias External validity: residents not representative of sample

Summary measures 13 Infection rates and measures of risk factors known to be related to infections.

Synthesis of results 14 See narrative Risk of bias across studies 15 Publication bias, selection bias Additional analyses 16 None Results Study selection 17 See Figure 1. Study characteristics 18 The majority of the studies were conducted in the United

States (n= 9; 37.5%); followed by Japan (n=7; 29.1%), Europe (n= 4; 16.7%), and Canada (n= 4; 16.7%). Overall, the majority were randomized control trials (n= 16; 67%), where the primary interest was to reduce respiratory infections (n=15; 62.5%) and focused on therapeutic interventions (n= 17; 70.8%).

Risk of bias within studies 19 Selection bias, inadequate allocation concealment, contamination risk, see narrative Randomization methods employed

Results of individual studies 20 Thirteen (54%) of 24 studies reported statistically significant results in favor of interventions on at least one of their outcome measures.

Synthesis of results 21 See narrative Risk of bias across studies 22 Publication bias, See narrative Additional analyses 23 None, conducted in tabular format Discussion Summary of evidence 24 The methodological quality of the available evidence

varied, and none of the included studies fulfilled all 28 criteria. The quality scores ranged from 11 to 27 out of 29 possible points. The majority of studies (n= 9; 37.5%) fell under fair quality. Alternatively, 7 studies were rated good and only 3 studies had excellent quality. Five studies received a score of 15 or less indicating poor quality. The mean quality assessment score of the averaged ratings between the 2 reviewers was 18.8.

Limitations 25 See narrative

Conclusions 26 Infection prevention in LTC facilities is an increasingly

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important area of research and yet significant gaps exist in the quality of interventions currently conducted. Future researchers and practitioners in LTC need to establish a comprehensive understanding of accurate and consistent measures for enhancing methodological clarity using clearly defined outcome measures and standardized reporting of findings

Funding Funding 27 This paper was supported by the National Institutes of

Health, National Institute of Nursing Research [T90 NR010824] and the Jonas Center for Nursing Excellence

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Appendix C. Downs and Black (1998) Quality Assessment Tool

Article (Author, Year):

Subscales Items Scores

Reporting 1. Is the hypothesis/aim/objective of the study clearly described?

Yes 1

No 0

2. Are the main outcomes to be measured clearly described in the Introduction or Methods Section?

Yes 1

No 0

3. Are the characteristics of the patients included in the study clearly described?(Inclusion/Exclusion Criteria are clear)

Yes 1

No 0

4. Are the interventions of interest clearly described?

Yes 1

No 0

5. Are the distributions of principal confounders in each group of subjects to be compared clearly described?

Yes 2

Partially 1

No 0

6. Are the main findings of the study clearly described?

Yes 1

No 0

7. Does the study provide estimates of the random variability in the data for the main outcomes?

Yes 1

No 0

8. Have all important adverse events that may be a consequence of the intervention been reported?

Yes 1

No 0

9. Have the characteristics of the participants lost to follow-up been described?

Yes 1

No 0

10. Have actual probability values been reported? (e.g., 0.035 rather than <0.05) for the main outcomes except where the probability value is less than 0.001?

Yes 1

No 0 Total /11

External Validity

11. Were the subjects asked to participate in the study representative of the entire population from which they were recruited?

Yes 1

No 0

Unable to determine

0

12. Were those subjects who were prepared to participate representative of the entire population from which they were recruited?

Yes 1

No 0

Unable to determine

0

13. Were the staff, places, and facilities where the participants were treated, representative of the treatment the majority of patients receive?

Yes 1

No 0

Unable to determine

0 Total /3

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Internal Validity-bias

14. Was an attempt made to blind study subjects to the intervention they have received?

Yes 1

No 0

Unable to determine

0

15. Was an attempt made to blind those measuring the main outcomes of the intervention?

Yes 1

No 0

Unable to determine

0

16. If any of the results of the study were based on “data dredging”, was this made clear?

Yes 1

No 0

Unable to determine

0

17. Do the analyses adjust for different lengths of follow-up of participants?

Yes 1

No 0

Unable to determine

0

18. Were the statistical tests used to assess the main outcomes appropriate?

Yes 1

No 0

Unable to determine

0

19. Was compliance with the interventions reliable?

Yes 1

No 0

Unable to determine

0

20. Were the main outcome measures used accurate (valid and reliable)?

Yes 1

No 0

Unable to determine

0 Total /7

Internal validity-Confounding (selection bias)

21. Were the participants in different intervention groups recruited from the same population?

Yes 1

No 0

Unable to determine

0

22. Were study subjects in different intervention groups recruited over the same period of time

Yes 1

No 0

Unable to determine

0

23. Were study subjects randomized to intervention groups?

Yes 1

No 0

Unable to determine

0

24. Was the randomized intervention assignment concealed from both participants and health care staff until recruitment was complete and irrevocable?

Yes 1

No 0

Unable to determine

0

25. Was there adequate adjustment for Yes 1

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confounding in the analyses from which the main findings were drawn?

No 0

Unable to determine

0

26. Were losses of participants to follow-up taken into account?

Yes 1

No 0

Unable to determine

0 Total /6

Power 27. Was a power calculation reported for the primary outcome?

Yes 1

No 0

Unable to determine

0

28. Did the study have sufficient power to detect a clinically important effect where the probability value for a difference being due to chance is less than 5%?

Yes 1 Total /2 No 0

Unable to determine

0

Grand Total: /29

Comments:

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Appendix D. Detailed Summary of Monthly Unit Level Nurse Workforce Characteristics (fy2003-2008)

Standard Deviation Range

Mean Between Within Min Max

CLC units n=180, 10,611 observations

Nursing Hours Per Resident Day (HPRD)(Hours)

Total Nursing HPRD 4.6 1.0 0.7 2.0 8.0

RN HPRD 1.5 0.6 0.3 0.2 5.5

LPN HPRD 1.2 0.5 0.3 0 4.8

NA HPRD 1.9 0.7 0.4 0 5.4

Contract HPRD 0.1 0.2 0.2 0 4.0

Percent of Total Nursing Hours Worked by Staff Type (%)

Percent RN 31.3 9.0 4.4 5.7 89.4

Percent LPN 25.8 9.5 4.6 0 72.6

Percent NA 41.5 12.6 5.7 0 79.5

Percent Contract 1.5 2.9 3.6 0 55.2

Nurse Tenure (Years)

Average Nursing Unit Tenure (includes RNs, LPNs, NAs)

4.3 1.0 0.7 0 9.3

Average RN Unit Tenure 4.7 1.4 0.9 0 11.0

Average LPN Unit Tenure 4.2 1.6 1.0 0 12.7

Average NA Unit Tenure 4.2 1.5 0.9 0 12.7

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Appendix E. Correlation Matrix of Independent Variables

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Appendix F. Effects of Staffing on Composite under Different Model Assumptions

Outcome:

Infection Composite

Main Model: Negative Binomial FE

Random Effects Model

Population Averaged

Model

Poisson FE Model

Total Nursing HPRD 1.000 1.002 1.008 1.012

(0.985) (0.830) (0.622) (0.435)

Percent RN 1.233 1.222 1.268 1.224

(0.264) (0.235) (0.398) (0.442)

Percent NA 1.160 1.064 1.078 1.215

(0.336) (0.646) (0.736) (0.344)

Percent Contract 0.986 0.910 1.094 1.175

(0.947) (0.633) (0.794) (0.565)

RN Unit Tenure **0.962 **0.963 **0.962 **0.958

(0.000) (0.000) (0.002) (0.001)

LPN Unit Tenure **0.980 0.989 0.996 0.987

(0.006) (0.106) (0.680) (0.248)

NA Unit Tenure 1.008 1.005 0.987 1.002

(0.340) (0.473) (0.283) (0.922)

Male 1.467 1.369 1.087 1.445

(0.167) (0.238) (0.855) (0.362)

Age 0.999 0.999 0.999 1.001

(0.865) (0.765) (0.838) (0.900)

Race 1.161 1.120 1.007 1.046

(0.282) (0.309) (0.971) (0.824)

RUG Score **5.770 **6.068 **4.962 **4.370

(0.000) (0.000) (0.000) (0.000)

ADL Index **1.070 **1.067 **1.051 **1.045

(0.000) (0.000) (0.000) (0.000)

Percent Short Stay **3.057 **3.139 **2.643 **2.353

(0.000) (0.000) (0.000) (0.000)

Admissions **0.994 **0.995 0.999 0.998

(0.000) (0.000) (0.761) (0.254)

Percent Dementia 1.067 1.001 1.015 1.023

(0.520) (0.994) (0.919) (0.889)

Percent Catheter -- -- **614.803 **336.816

-- (0.000) (0.000)

Percent Turn **1.250 **1.223 1.087 1.147

(0.001) (0.001) (0.441) (0.297)

Percent Vent **42.106 1.867 **0.034 1.125

(0.008) (0.531) (0.006) (0.921)

Notes. Coefficients are Incident Rate Ratios (IRRs), p-values in parentheses below IRRs; * Significant at p<0.05 **Significant at p<0.01 FE= Fixed Effects, Composite= Sum count of urinary tract infections, pneumonia, and pressure ulcers Main Model= Negative Binomial Fixed Effects; Random Effects Model= Negative Binomial Random Effects; Population Averaged Model= Negative Binomial Population Averaged Model, Poisson Model= Poisson Fixed Effects with robust standard errors; Monthly time dummies were included in all models; output not shown. Hausman Test showed p<0.001 indicating to reject Random Effects Model in favor of Fixed Effects Model.

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Technical Appendix 1: Regression Model Justification

Upon examining descriptive statistics and bivariate correlations, the following monthly

unit-level fixed effects model was developed:

YInfection= β0 + RCijβ1 + UCijβ2 + NWijβ3 + Pijβ4+ε

In the above equation 1), YInfection is a latent variable that governs whether the ith

resident

in the jth

unit acquires an infection, and Y is the observed infection (Urinary tract infection,

pneumonia, pressure ulcer). The models include a vector of resident demographics and

information such as resident functional status (RC), a vector of unit characteristics (UC) at which

the resident received care, a vector for nurse workforce characteristics (NW) and a vector of

infection prevention processes associated with nursing care (P). The βs are coefficients and ε is

the error term. Separate regressions were modeled for each infection type; however, an overall

composite combining the 3 infection outcomes are presented because all of these outcomes

indicate resident adverse events and because the results were similar to when they were

examined individually.

A fixed effects model was chosen for 3 reasons: 1) to control for any time-invariant

attributes of the unit (e.g., bed size, location), 2) to control for unobservable attributes of the unit

(e.g., good nurse manager vs. bad nurse manager) and 3) to control for instances in which such

time-invariant unobservable attributes may impact resident outcomes (i.e., correlated with the

outcome). The intentions for this analysis were not to make any comments about whether high

versus low nurse staffing is better. Instead, the fixed effects analysis provided interpretation that

for any given NH unit, when compared to the unit’s norm how the outcome changes when nurse

workforce characteristics either go up (increase nurse tenure) or down (decrease nurse tenure). In

other words, each NH unit acts as its own control and inferences can be made about how changes

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within the units across time affect outcomes. When not including fixed effects, the estimators are

contaminated by not including unobservable variables whose effects do not change across time

and therefore risk potential omitted variable bias (Allison, 2005; Cameron and Trivedi, 2010).

Because the count of infections followed a negative binomial distribution (variance

exceeding the mean), the negative binomial model was used. Monthly time dummies were

included to control for time trends.

To further assess our modeling assumptions, 3 alternative models were examined: 1)

Negative Binomial Population Averaged Model (XTGEE), 2) Poisson Fixed Effects Model (XT

Poisson FE) and 3) Negative Binomial Random Effects Model (NBREG RE). The Hausman test

was performed following the random effects model. The Hausman test yielded significant results

(p<0.001) and ruled in favor of a fixed effects model. Comparing the incident rate ratios (IRRs)

and p-values across the 3 models, RN tenure was a robust finding; however, LPN tenure was not

significant in the 3 alternative models.

From previous studies showing how organizational culture and teamwork on a unit (i.e.,

time invariant attributes) can impact quality, we believe that there are indeed unobservable

factors which likely contribute to the quality of care in NHs; we therefore made the decision to

conduct fixed effects analyses. While results were similar between the alternative models, only

fixed effects controls for unobservable heterogeneity and helps to control for omitted variable

bias by having individual units serve as their own controls. Because a fixed effects allows one to

control for all unobservable and time invariant attributes of a unit, it therefore allows estimation

of within unit changes; a random effects model does not meet such assumptions.

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Therefore, without fixed effects, we may be overstating the true effects, but with fixed

effects we may be understating the truth and in this case underestimating the true effects of RN

tenure. The highly significant coefficients for RN tenure and LPN tenure in our model are

therefore conservative. Because we wanted to take into account such unmeasurable attributes

(e.g., organizational culture) that likely differ across units but are likely to remain stable across

time within a unit makes the fixed-effects model the correct choice.