The Nurse Practitioner Workforce in Six Countries: Size ... · In order to assess the potential of Nurse Practitioners (NP) in alleviating shortages and expand access, we analyzed

For peer review only

The Nurse Practitioner Workforce in Six Countries: Size,

Growth, Physician Substitution Potential

Journal: BMJ Open

Manuscript ID bmjopen-2016-011901

Article Type: Research

Date Submitted by the Author: 14-Mar-2016

Complete List of Authors: Maier, Claudia; University of Pennsylvania, Center for Health Outcomes and Policy Research, School of Nursing; Technische Universitat Berlin, Department of Healthcare Management Barnes, Hilary; University of Pennsylvania, Center for Health Outcomes and Policy Research, School of Nursing Aiken, Linda; University of Pennslvania, Center for Health Outcomes and Policy Research, School of Nursing Busse, Reinhard; Technische Universität Berlin, Department of Health Care

Management

<b>Primary Subject Heading</b>:

Nursing

Secondary Subject Heading: Global health

Keywords: nursing, health workforce, physicians, PRIMARY CARE

For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml

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The Nurse Practitioner Workforce in Six Countries: Size, Growth, Physician

Substitution Potential

Corresponding author: Claudia B Maiera) b), MSc

a) Harkness & B. Braun Fellow in Healthcare Policy and Practice

Center for Health Outcomes and Policy Research

University of Pennsylvania, School of Nursing

Claire Fagin Hall

418 Curie Blvd

Philadelphia, PA 19104-4217; b) Department of Healthcare Management,

Technische Universität Berlin, Germany

Administrative office H80

Str. des 17. Juni 135

10623 Berlin, Germany

Phone: +49 176 32944628

Fax: +49 30 314 28433

[email protected]

[email protected]

Hilary Barnes, PhD, CRNP

Postdoctoral Research Fellow


University of Pennsylvania

418 Curie Blvd

Claire M. Fagin Hall, 388R

Philadelphia, PA 19104-4217

Phone: +1 215-898-4908

Fax: +1 215-573-2062

[email protected]

Linda H Aiken, PhD, RN

Claire M Fagin Professor and Director



418 Curie Blvd



Phone: +1 215-898-9759

Fax: + 215-573-2062

[email protected]

Reinhard Busse, PhD, MD, MPH, FFPH

Head of the Department of Health Care Management

Faculty of Economics and Management

Head of the Berlin hub of the European Health Observatory on Health Systems and Policies

Technische Universität Berlin


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Phone: +49 30 314 28420

Fax: +49 30 314 28433

[email protected]

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ABSTRACT

Objectives. Many countries are facing provider shortages in primary care or are projecting

shortfalls for the future. In order to assess the potential of Nurse Practitioners (NP) in

alleviating shortages and expand access, we analyzed the size, annual growth (2005-2015),

and the extent of advanced practice of NPs in six Organisation for Economic Cooperation and

Development (OECD) countries.

Design. Cross-country data analysis of national nursing registries, regulatory bodies, and

statistical offices data; as well as OECD health workforce and population data.

Setting/Participants. NP and physician workforces in six OECD countries (Australia,

Canada, Ireland, Netherlands, New Zealand, United States).

Primary and secondary outcome measures. The main outcomes were the absolute and

relative number of NPs per 100,000 population compared to the nursing and physician

workforces; the Compound Annual Growth Rates (CAGR), annual and median percentage

change from 2005-2015; and the extent of advanced clinical practice measured by physician

substitution effect.

Results. The United States showed the highest absolute number of NPs and rate per

population (40.5 per 100,000 population), followed by the Netherlands and Canada (12.6 and

9.8), Australia (4.4), and Ireland and New Zealand (3.1, respectively). Annual growth rates

were high in all countries, ranging from annual compound rates of 6.1% in the United States

to 27.8% in the Netherlands. Growth rates were between three- and nine-times higher

compared to physicians. Finally, empirical studies suggested that NPs are able to provide 67-

90% of all primary care services.

Conclusions. NPs are a rapidly growing workforce with high levels of advanced practice

holding future potential to filling gaps or shortages, particularly in primary care. Workforce

monitoring based on accurate data is critical to inform educational capacity and workforce

planning. Including routine data in international workforce databases would improve data

availability globally.

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Strengths and limitations of this study

• This is the first international study to determine the total and relative size of Nurse

Practitioners per 100,000 population in comparison to physicians in six OECD

countries.

• A strength of this study is the analysis of comprehensive and largely unexplored data

from authoritative sources in the six countries.

• Annual growth rates were calculated for 2005-2015 using compound annual growth

rates (CAGR), annual and median percentage changes, to account for excessive yearly

changes found.

• The study faces limitations as to data variability of the activity levels of NPs and

physicians, yet, for within-country comparisons, we used consistently the same

activity levels for NPs and physicians.

• While there is limited empirical research on the substitution effect of NPs for

physicians in the six countries studied, findings show that NPs work at high levels of

advanced practice.

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BACKGROUND

Health workforce shortages and geographical imbalances exist in many countries worldwide

(1). The World Health Organization has estimated a deficit of 7.2 million health professionals

globally (2). The United States (U.S.) projected a shortfall of 44,000 primary care physicians

by 2035 (3) and the European Commission has estimated a shortage of 1 million health

professionals by the year 2020 (4). While educating more physicians is one workforce

strategy, countries are also investing increasingly in a highly qualified nursing workforce,

such as Advanced Practice Nurses or Nurse Practitioners (APN/NP), with usually Master’s

level education (5). Expanding the roles of nurses combined with task-shifting from

physicians to nurses as suggested by the World Health Organization, has received policy

attention to respond to shortages (6, 7).

There is a consistent body of evidence showing that nurses with advanced education can

provide high-quality care that is comparable to physicians for a range of acute and chronic

illnesses (8-11). The U.S. was the first country to introduce NPs in 1965, followed by Canada

in 1967 (12, 13). Other countries have more recently introduced NPs, including the United

Kingdom (U.K.), Ireland, the Netherlands, Australia and New Zealand (14-18).

The extent to which NPs are effective in addressing shortages depends on the scale of this

workforce, and its integration and implementation in healthcare (19). Scale in this context

refers to two factors, a sufficient numerical size of NPs and the extent of advanced practice.

Both elements are critical to assess the contribution of the workforce.

Few international research exists on the size of the NP workforce. The international literature

has compared primarily NP education, governance and regulation of titles (20-24). In an

overview of the primary care workforce in six countries, the total number of NPs was found to

be low in most countries (25). However, the study only provided the total number of

providers, no further information on its relative size compared to other professions or time

trends. At the individual country-levels, many studies exist, particularly in the U.S. that aim to

quantify the total number of NPs, by employment, specialty and clinical practice area (26-29).

They found that the various data sources provide a patchy overview in the U.S., particularly

when focusing on the clinically active NPs and specialty areas (26). The comparatively fewer

studies on the size of NPs in Canada, Australia, and New Zealand found that the workforce is

small, but provided limited information beyond the number of providers (30, 31).

While NPs perform a substantially expanded range of clinical services, there is limited

knowledge on the detailed level of advanced practice. Conceptually, the substitution effect of

physicians by NPs refers to the quantification of how many patients or services in a particular

care setting can be performed by NPs that are usually provided by physicians (32, 33). In a

systematic review, 30-70% of clinical activities of physicians were found could be taken over

by NPs, however, most of the included studies were conducted in the 1970s and 1980s (32).

NPs’ roles have expanded internationally, hence an update of the literature is relevant to

estimate the extent of advanced practice and variations across countries.

This is the first study to assess the scale of NPs, growth rates and the extent of advanced

practice compared to physicians, using a cross-country comparative study design. The study

pursued the following three research questions: 1) to analyze the absolute and relative size of

the NP workforce in six OECD countries (Australia, Canada, Ireland, the Netherlands, New

Zealand, and the U.S.), focusing on practicing NPs, their proportion of the total nursing

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workforce and rates per 100,000 population relative to the physician workforce; 2) to examine

time trends from 2005-2015 in the NP compared to the physician workforces; and 3) to

estimate the extent of advanced practice in primary care measured by a concept referred to as

physician ‘substitution effect’.

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METHODS

Definitions and outcome measures

In order to assess the absolute and relative size of the NP workforce, we followed the OECD

definition of activity levels of health professions: (i) practicing professionals (providing direct

patient care), (ii) professionally active (providing direct patient care, plus working in related

administration, management or research as part of the profession), and (iii) registered/licensed

to practice (authorized to practice, including practicing, professionally active and non-

practicing providers) (34). For this study, the activity status practicing NPs was preferred over

professionally active and registered/licensed, following the OECD (34). In countries with no

available information on the number of practicing NPs, data on professionally active or

registered was used.

To analyze time trends, we compared the yearly growth rates of NPs to physicians from 2005

to 2015 where available. We chose the physician profession as comparator for two reasons.

First, to compare the growth rates to estimate the potential in alleviating physician shortages

and second, since OECD data on time trends are of better quality and comparability than

those for the nursing profession.

To answer the research question on NPs levels of advanced practice, we performed a literature

scoping review, following the concept referred to as ‘substitution effect’, which estimates the

potential of a new, extended professional role in taking up activities of an established

profession (32).

First phase: identification of countries and data availability - the TaskShift2Nurses

Study

We identified countries with APN/NPs based on an expert survey in 39 industrialized

countries (Task-Shift2Nurses Study 2015). Information on the survey itself, its sampling

strategy, data collection and analysis is provided elsewhere (forthcoming, (23)). A total of 93

country experts participated (response rate 85.3%). The survey included questions on scope of

practice and education, data availability, existence of nursing registries, and mandatory vs.

voluntary registration policies, among others. Institutional Review Board (IRB) approval was

obtained at the University of Pennsylvania.

The TaskShift2Nurses study identified eleven countries with APN/NPs: Australia, Canada,

Finland, Ireland, Netherlands, England, Northern Ireland, Scotland, Wales, New Zealand and

the U.S (23). Definitions used were existence of APN/NPs, education at APN/NP level and

advanced practice focusing on primary care, measured by seven clinical activities: authority to

prescribe medications, ordering medical tests, decide on medical treatment,

diagnosis/advanced health assessment, referrals, responsibility for a panel of patients, and first

point of contact (5).

For the purpose of this study, in a subsequent step we contacted country experts individually

to obtain further information on data sources and holders. The countries within the United

Kingdom and Finland were excluded from this study, because no registry data or other

national or subnational data sources on APN/NPs were identified.

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Second phase: country-specific secondary data collection

In a subsequent step, we retrieved secondary data on NPs for the remaining six countries from

authoritative sources as advised by country experts. All six countries had NPs or similar roles

working in advanced practice, of which the titles were regulated and registration was

mandatory. The secondary data collection phase took place between August 2015 and January

2016. These sources included nursing boards or councils (Australia, Ireland, New Zealand),

an institute on health information (Canada), and a nurse specialist registry

(Registratiecommissie Specialismen Verpleegkunde, RSV) in the Netherlands. In the

Netherlands, Nurse Specialists (Verpleegkundig Specialisten) are sometimes referred to as

NPs in English literature (15), however, we decided to keep the translation closest to its

original title, since this title is regulated.

In the U.S., several data sources were reviewed for suitability, including data from the Kaiser

Family Foundation (KFF) (35), American Association of Nurse Practitioners (AANP) (36),

and the U.S. Bureau of Labor Statistics (37-39). Challenges of the U.S. data include the co-

existence of multiple sources which calculate the workforce differently. The KFF provided

data on professionally active NPs based on active state NP licenses, however, no data on time

trends were available. The AANP data cover NPs licensed to practice; however, these data are

estimated and actual numbers not available to the public. The U.S. Bureau of Labor Statistics

estimates the professionally active NP workforce, but NP-specific data are only available

since 2012 and exclude self-employed NPs (37-39). We chose for each of the research

questions the most accurate data source highlighting their strengths and weaknesses.

Canada and New Zealand had data on time series available for all years since 2005, whereas

the Netherlands had data since 2009, the year of introduction of the specialist registry, Ireland

since 2010 and Australia since 2012.

Third phase: literature review on the extent of advanced practice

In addition to the secondary data analysis, we conducted a comprehensive literature review,

covering Medline, CINAHL, Google Scholar, and grey literature, to identify studies on

substitution effect/extent of advanced practice. Studies were included if they used the a

method to quantify the extent of advanced practice, also referred to as physician “substitution

effect”, defined as the percentage of typical physician-provided activities that can be officially

and safely performed by NPs or the percentage of all services that can be safely provided by

NPs (32, 40). Search terms included various combinations of the terms substitution, nurse

practitioner, extent of advanced practice, scope of practice, among others. The search was

conducted in English, plus we contacted country experts for additional, grey literature.

Inclusion criteria were studies conducted in one of our six countries that empirically analyzed

the extent of advanced practice of NPs compared to physicians or percentage of all services

that were provided by NPs.

Data analysis

Regarding research question 1, we calculated NP rates per 100,000 population using the

population sizes provided by the OECD 2015 population statistics online database (41). To

compare the density of NPs with physicians, we retrieved the physician ratios per 1,000 from

the OECD database, which we subsequently multiplied by 100 to obtain rates per 100,000

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population (42). Data on the nursing workforce was retrieved from the same data holders from

which the data on NPs were obtained, except for the Netherlands where nurse specialists are

registered in a separate registry (43).

As for research question 2 on time trends, we calculated the yearly percentage change of NPs

and physicians (e.g. 2005-06, 2006-07), covering 2005 to 2015 or years available, to assess

the relative growth of the APN/NP profession compared to the physician profession.

Percentage change is a method derived from demographics (44). It is based on the calculation

of the absolute difference at two points in time and divided by the original group size,

multiplied by 100. This method allows to quantify the increase or decrease over time periods

irrespective of groups’ differences in size. In addition to yearly percentage changes, we

calculated the Compound Annual Growth Rates (CAGR) which is commonly used in

comparison of time trends (45-47), since it smoothes yearly growth rates over time. In

addition, we calculated the average and median percentage change across the entire time

period for each of the country and profession covered (34).

Regarding research question 3, all studies identified from the literature scoping review were

reviewed according to inclusion and exclusion criteria. Studies were included if the concept of

substitution was applied calculating the percent of substitution effect, provided the study was

implemented in one of the six countries. We subsequently extracted the numerical results of

the percentage of all services that NPs were able to provide or percentage of physician

services that could be taken over by NPs, depending on the service delivery setting and

location, but focusing on primary care. We excluded simulations or projections of the

potential substitution effect.

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RESULTS

Total and relative size of the Nurse Practitioner workforce

The United States showed the largest number of professionally active NPs (N= 174,943)

compared to the other five OECD countries, which represented 5.6% of its total active U.S.

nursing workforce in 2015 (35) (Figure 1). In the Netherlands and Canada, both the total and

relative size was lower, percentages were 1.5% and 1.3% respectively, based on data on

registered NPs in the Netherlands and practicing NPs in Canada. In Australia, New Zealand

and Ireland, the relative sizes were very small, 0.5% and less.

[Figure 1: Total number of NPs and % of professional nursing workforces, 2015*]

Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following secondary data

sources: (35, 43, 48-52),

Notes: *2015: except for Canada, Ireland: 2014; Data on RNs include NPs, U.S.=United States, NP= Nurse

Practitioner, N=total number, P=Practicing, PA=Professionally Active, R=Registered/Licensed to practice,

RNs=Registered Nurses, Caveats: Netherlands (nurse specialists): an estimated 12 test accounts are in the

database (0.4%) that cannot be filtered out (personal communication, with registry advisor at Verpleegkundig

Specialisten Register, 29 January 2016).

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Results regarding the workforce density per population showed similar patterns across the six

countries (Figure 2). The rate of NPs in the United States was highest, at 40.5 practicing NPs

per 100,000 population (41, 53) based on 2012 data to allow for comparisons with physicians.

NPs were less than one fifth of the U.S. physician workforce (41, 42).

In the Netherlands and Canada, rates were considerably lower compared to the U.S. at 12.6

and 9.8 per 100,000 population. Compared to physicians, Australia, Ireland and New Zealand

showed very low rates.

[Figure 2: Nurse Practitioner density compared to physicians per 100,000 population, 2013*]

Sources: Authors’ calculations, based on the following data sources: (35, 48-53), Data on physicians based on

OECD 2015 database (42)

Notes: *Year 2013; except for Ireland (2014), United States (2012) depending on years covered by OECD

physician data; NPs= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active,

R=Registered/Licensed to practice, U.S.=United States, Caveats: Netherlands (Nurse specialists): an estimated

12 test accounts are in the database that cannot be filtered out (personal communication, with registry advisor at

Verpleegkundig Specialisten Register, 29 January 2016).

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Growth of the Nurse Practitioner workforce from 2005-2015

All countries showed a continuous growth of their NP workforce from 2005 to 2015 or those

years available (Table 1). However, growth rates varied considerably across countries; and

within countries between NPs and physicians.

In the U.S., NPs licensed to practice increased from an estimated 106,000 in 2004 to 192,000

in 2014 (36). Rates per 100,000 population increased from 35.87 to 60.22 NPs per 100,000

population. Data on professionally active NPs showed an increase from 105,780 to 122,050

NPs, yet were only available from 2012 to 2014 (37-39).

In the Netherlands, the numbers of Nurse Specialists registered increased rapidly, from 140 in

2009 to 2,749 in 2015. The rate of Nurse Specialists per 100,000 population in the

Netherlands showed the most rapid increase of all countries studied, more than 14-fold, from

0.85 Nurse Specialists in 2009 to 14.74 Nurse Specialists per 100,000 in 2014.

In Canada, the rate of NPs per 100,000 increased from 2.9 in 2005 to 10.7 in 2014, more than

three-fold. In Australia, the NP rate increased from 3.5 in 2012 to 5 per 100,000 population in

2014. Although a rapid increase took place in New Zealand from 0.3 in 2005 to 3.1 in 2014,

and in Ireland from 0.8 in 2010 to 3.1 in 2014, total numbers remained at low levels.

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Nurse Practitioner compared to physician growth rates

We present compound annual growth rates (CAGR), and the median percentage changes over

the 2005-2015 period to show differences in the calculation methods (table 2). In order to

account for the extremly high growth rates in the first year in the Netherlands and Ireland due

to the small numbers (Netherlands: 2009-10, Ireland: 2010-11), we calculated the CAGR for

the full period and the CAGR without the first year for the two countries.

Growth among NPs was high in all countries, and consistently and considerably higher than

among physicians. The compound growth rate among Nurse Specialists in the Netherlands

was 27.8% (CAGR 2010-2015), the highest of all six countries. The yearly growth was higher

than that of its medical workforce at 2.9%, overall yearly growth was more than 9-times

higher. In New Zealand and Canada, compound annual growth of NPs was 27.3% and 16.7%

respectively, approximately nine- and five-times higher than that of their medical workforces

(2.8%, and 3.3%). Ireland showed a comparatively lower yearly increase of its NP workforce,

yet, still a more than four-times growth compared to its physician workforce. Of the six

countries, the United States had the lowest annual compound growth of 6.1% or 7.4%

annually depending on the data sources, yet, was still more than three-times higher than that

of physicians (36-39, 41, 42).

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Table 1: Total number of Nurse Practitioners and Physicians, six countries, 2005-2015 (or years available)

Sources: authors’ calculations, based on the following data sources (36-39, 42, 48-52, 54-63),

Notes: NP=Nurse Practitioners, NS=Nurse Specialists, MD=Medical Doctors/Physicians, P=Practicing, PA=Professionally Active, R=Registered, ..= not available, Caveats: United States: *data on

professionally active Nurse Practitioners do not include self-employed, hence underestimate totals (37), ^year 2004 (in lieu of 2005 data availability) e= data on registered NPs are estimates, exact

numbers are not publicly available (36), Netherlands: Data on nurse specialists (NS, R) include approximately 10 invalid cases per year used as test accounts (range 8-12) in the database that cannot

be filtered out (estimated 8 cases yearly in 2009/2010/2011/2012 and 12 in 2013/2014/2015) (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January

2016), Canada: OECD data on MDs, based on two combined data sources, which may overstate the number of physicians, since interns and residents may be registered twice, Australia: break in OECD time series data on MDs in 2010, due to change of data holders. (64, 65)

Year United States Canada Netherlands Australia New Zealand Ireland

NP NP MD NP MD NS MD NP MD NP MD NP MD

PA R R PA PA R R R R R R PA PA

2005 .. 106,000e^ 902,053 943 69,619 .. 55,673 .. 67,890 14 11,555 .. ..

2006 .. .. 921,904 1,129 70,870 .. 57,098 .. 71,740 21 11,889 .. 11,617

2007 .. 120,000e 941,304 1,344 72,903 .. 58,661 .. 77,193 30 12,318 .. 12,311

2008 .. .. 954,224 1,626 75,155 .. 60,300 .. 78,909 46 12,746 .. 13,022

2009 .. 130,000e 972,376 1,990 78,623 140 62,057 .. 82,895 50 13,176 .. 13,663

2010 .. 140,000e 985,375 2,486 80,895 807 63,585 .. .. 72 13,398 38 14,029

2011 .. 148,000e 1,004,635 2,777 84,313 1,272 65,568 .. 87,790 91 14,021 97 14,814

2012 105,780* 157,000e 1,026,788 3,157 87,306 1,847 68,119 788 91,504 103 14,280 109 14,498

2013 113,370* 171,000e 1,045,910 3,477 90,205 2,124 69,942 1,004 91,467 117 14,596 123 14,054

2014 122,050* 192,000e .. 3,786 .. 2,480 .. 1,165 .. 138 14,787 141 14,016

2015 .. .. .. .. .. 2,749 .. 1,214 .. 157 .. .. ..

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Table 2: Annual growth of the nurse practitioner and physician workforces, measured by yearly percentage change (%), median percentage change

and Compound Annual Growth Rate (CAGR, %), in six countries, 2005-2015 (or years available)

Sources: authors’ calculations, based on the following data sources (36-39, 42, 48-52, 54-63)

Notes: CAGR=Compound Annual Growth Rate, [1]=CAGR (2004/2015) calculated based on 2004-2014 data (2004 data used in lieu of missing 2005 data) [2]=CAGR (2010-2015), 2009-10 was

excluded due to excessive growth rate caused by small numbers (CAGR 2009-2015: 64.3%, not shown), [3]=CAGR (2011-2014), 2010-11 data excluded (CAGR 2010-14: 38.8%, not shown),

PC=Percentage Change, NP=Nurse Practitioners, NS=Nurse Specialists, MD=Medical Doctors/Physicians, P=Practicing, PA=Professionally Active, R=Registered, ..= not available, Caveats:

United States: *data on professionally active Nurse Practitioners do not include self-employed (37). °Data on registered NPs are estimates, exact numbers are not publicly available (36),

Netherlands: Data on nurse specialists (NS, R) include approximately 10 invalid cases per year used as test accounts (range 8-12) in the database that cannot be filtered out (estimated 8 cases yearly

in 2009/2010/2011/2012 and 12 in 2013/2014/2015) (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January 2016), Canada: OECD data on MDs,

based on two combined data sources, which may overstate the number of physicians, since interns and residents may be registered twice, Australia: break in OECD time series data on MDs in 2010,

due to change of data holders. (64, 65)



PA* R° R PA PA R R R R R R PA PA

2005-2006 .. ..^ 2.2% 19.7% 1.8% .. 2.6% .. 5.7% 50.0% 2.9% .. ..

2006-2007 .. .. 2.1% 19.0% 2.9% .. 2.7% .. 7.6% 42.9% 3.6% .. 6.0%

2007-2008 .. ..^ 1.4% 21.0% 3.1% .. 2.8% .. 2.2% 53.3% 3.5% .. 5.8%

2008-2009 .. .. 1.9% 22.4% 4.6% .. 2.9% .. 5.1% 8.7% 3.4% .. 4.9%

2009-2010 .. 7.7% 1.3% 24.9% 2.9% 476.4% 2.5% .. .. 44.0% 1.7% .. 2.7%

2010-2011 .. 5.7% 2.0% 11.7% 4.2% 57.6% 3.1% .. .. 26.4% 4.6% 155.3% 5.6%

2011-2012 .. 6.1% 2.2% 13.7% 3.5% 45.2% 3.9% .. 4.2% 13.2% 1.8% 12.4% -2.1%

2012-2013 7.2% 8.9% 1.9% 10.1% 3.3% 15.0% 2.7% 27.4% 0% 13.6% 2.2% 12.8% -3.1%

2013-2014 7.7% 12.3 .. 8.9% .. 16.8% .. 16.0% .. 17.9% 1.3% 14.6% -0.3%

2014-2015 .. .. .. .. .. 10.9% .. 4.2% .. 13.8% .. .. ..

Median PC 7.5% 7.7% 2% 19.0% 3.2% 30.1% 2.8% 16.0% 4.7% 22.2% 2.9% 13.7% 3.8%

CAGR 7.4% 6.1%[1] 1.9% 16.7% 3.3% 27.8%[2] 2.9% 15.5% 5.1% 27.3% 2.8% 13.3%[3] 2.4%

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16

Extent of advanced clinical practice

The five studies identified that quantified the extent of clinical practice of NPs were

conducted in the U.S., Canada and the Netherlands (Table 3). No studies conducted in the

three other countries were identified. The five studies found NPs able to provide between 67%

and 90% of primary care services. Differences existed within and across countries, suggesting

that within countries, service delivery settings, rural versus non-rural areas, education and

practice profiles may play a role. Most studies were based on small sample sizes and/or

conducted more than 30 years ago (66-68), whereas one recent studies with a larger sample

size was identified (29).

Table 3: Level of advanced clinical practice, measured by physician “substitution” effect

of nurse practitioners

Country Extent of advanced practice (% of all services or % of

physician substitution effect)

Sources

Australia n/a

Canada 67% of all primary care patient visits provided by NPs

(66)

Ireland n/a

New Zealand n/a

Netherlands 75-83% of clinical activities in out-of-hours primary

care settings (weekend shifts in GP practices) could be

taken over by Nurse Specialists (Verpleegkundig

Specialist)

(68, 69)

United States 75% of adult primary care can be provided by NPs

90% of pediatric primary care can be provided by NPs

75% of primary care visits in rural settings

(67)

(29)

Sources: provided in table

Notes: n/a= not available (no relevant studies identified)

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DISCUSSION

The size of the NP workforce in the six countries studied is variable, but growing rapidly,

with high levels of practice in primary care. The U.S. is the only country where the NP

workforce has reached a considerable density of 40.5 practicing NPs per 100,000 population,

in other countries the workforce is smaller, ranging from 12.6 per 100,000 population in the

Netherlands to low levels in New Zealand and Ireland. Yet, the workforce has rapidly and

consistently grown since 2005 in all countries, at much higher rates than the physician

workforce. Moreover, empirical studies show the large and wide range of advanced clinical

activities that NPs can provide. Depending on the country, provider models and settings, the

studies suggest that between 67 and 90% of primary care services can be safely provided by

NPs. Taken together, the findings demonstrate that the NP workforce has a high future

potential in filling unmet care needs and alleviating shortages in primary care.

Our study is the first of its kind to analyze the size and rate of NPs across six countries, and

set yearly growth in comparison with physicians. Yet, the study also faces several limitations.

First, data sources varied in the activity levels covered, e.g. practicing, professionally active

or registered NPs and physicians, which limits cross-country comparability. This limitation is

faced by all international data on health workforces, including the OECD and WHO, since

countries use different registration policies and data collection methodologies. However, for

within-country comparisons, we consistently compared the same activity levels of NPs and

physicians. In the U.S. decentralized approach to licensing of NPs, several different data

sources and holders were identified, with large differences across data in terms of size, active

levels and overall quality of data. Due to state-level authority over licensing procedures, data

may include double counting of NPs. Moreover, data on time trends of ten years were based

on estimates and covered the licensed workforce. Hence, the U.S. data can at best be

approximations to the actual number of practicing NPs over the ten-year period.

Our results are largely in line with one international study showing the relatively small scale

of the NP workforce (25). Reasons for the differences between the scale of the NP workforce

in the U.S. and other countries have not been empirically validated. It is assumed they may be

multifactorial. Not only the years of existence may play a role, as the U.S. was the first

country to implement NPs in 1965, but other factors may also influence their size and growth.

Canada introduced the first NPs only two years later, but relies on a much lower total number

and density of NPs than the U.S. Reasons for a small NP base in Canada have been discussed,

and include limited role clarity, differences across provinces and territories in education, and

challenges in creating positions for NPs (13, 30, 70). In Australia, NPs got access to the

Medical and Pharmaceutical Benefits Scheme in 2010, easing their practice, yet there are still

a number of policies impacting scope of practice (71, 72). Reasons for the low numbers in

New Zealand and Ireland include a younger existence of NPs dating back to the 2000s, and

high entry-level requirements (14, 56, 73, 74).

Time series data showed a considerable increase of NPs in all countries studied, much higher

yearly growth than found in the medical workforces. This trend may partially but not entirely

be related to the fact that increases in very small numbers result in large growth rates. We

took account of this by excluding extreme values from the CAGR calculations for Ireland and

the Netherlands, and calculated median percentage changes which were comparable to

CAGR.

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The continuous and higher growth rates point to an emerging NP workforce that has not

reached its full numerical potential, as compared to professions with a longer tradition, such

as the physician workforce. Many countries in our study have removed or eased regulatory

barriers to advance practice, such as in Australia, which granted NPs’ access to the

pharmaceutical and medical benefits scheme in 2010 (75). New Zealand expanded

prescriptive authority for NPs in 2014 (76)), and the Netherlands has regulated the Nurse

Specialist profession in 2009 and expanding scope of practice in 2012 (77). In the U.S., an

increasing number of states have removed regulatory barriers over the last decade (78).

Moreover, medical student intake or residency places are restricted by some sort of quota

system or numerus clausus in all countries, to avoid an excessive medical workforce and at

the same time, physician shortages (79). These regulatory measures may explain the moderate

annual increase among the medical workforce. To which extent countries’ workforce planning

take account of NPs or other APNs to project student intake, has received little attention in

research and practice.

Our findings on the level and extent of advanced practice show that NPs could covered a

range of approximately 67 to 90% of all primary care services. Findings are largely in line

with a report by the American College of Physicians, suggesting that 60-90% of primary care

can be provided by NPs (80). Our findings confirm and suggests that NPs scope of practice

may have expanded compared to a previous review, that showed a lower range of 30% to 70%

of physician-provided activities that could be taken over by NPs (32).

This study shows a rapid yearly increase of the NP workforce, which suggests more attention

should be paid to its future potential to expand capacity and alleviate shortages. To date, data

on the NP workforce is not covered in international health workforce databases, neither by

WHO or OECD, nor the international or European nursing associations. Most data is publicly

available or available upon request from the respective nursing regulatory bodies’ websites or

other data holders.. In the United States with the numerically largest workforce, data

availability is limited, a barrier for the monitoring of the workforce. Integrating NPs in health

workforce data and intelligence systems at national and international level is therefore critical

for their development, education and deployment.

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CONCLUSIONS

Nurse Practitioners are a rapidly growing workforce internationally. If growth rates continue,

this workforce will increase considerably in the future and holds potential in alleviating

physician shortages or reducing waiting time, particularly in primary care. To date, NPs are

not included in international workforce databases, hence, the overall size of the workforce and

changes over time go unnoticed. Yet, data are available for NPs in most countries as

registration is mandatory. As this workforce grows, using routine data will become critical to

monitor NPs as part of the overall health workforce, in order to inform educational capacity,

workforce projections and planning.

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a) Contributorship statement

CBM had the main role in the study design, data collection, and analysis, and wrote the

manuscript. HB contributed to the identification of U.S. data and the literature review, and

was involved in the revisions of the manuscript. LHA and RB gave overall guidance on the

study, the methodology, and reviewed the paper. All authors read, commented upon, and

approved the final manuscript.

Acknowledgements: We are grateful to the Dutch Registration Commission for Nurse

Specialists in the Netherlands (Registratiecommissie Specialismen Verpleegkunde, RSV) for

their support in providing time series data and important additional contextual information.

Moreover, we thank the 93 country experts who participated in the survey. In particular, we

thank the following country experts for providing additional information on secondary data

sources: Julianne Bryce, Australian Nursing and Midwifery Federation; Miranda Laurant,

HAN University of Applied Sciences, Faculty of Health and Social Studies, the Netherlands;

Marieke Kroezen, Catholic University Leuven, Belgium; Jenny Carryer, Massey University

and College of Nurses, New Zealand; Anne-Marie Brady, Trinity College Dublin, Republic of

Ireland; Barbara Todd, Hospital University of Pennsylvania; Kenneth Miller, American

Association of Nurse Practitioners.

b) Competing interests

All authors have completed the ICMJE uniform disclosure form at

www.icmje.org/coi_disclosure.pdf and declare: CB Maier had financial support for the

TaskShift2Nurses Study from the Commonwealth Fund and B. Braun Foundation, through

the Harkness Fellowship. The two funders had no role in the research. The authors did not

have financial relationships with any other organisation that might have an interest in the

submitted work, nor do they possess any other relationships or activities that may have

influenced the submitted work.

c) Funding

This work was supported by The Commonwealth Fund and the B. Braun Foundation, through

the Harkness Fellowship. The views presented here are those of the authors and should not be

attributed to the The Commonwealth Fund or B. Braun Foundation and their directors,

officers, or staff.

d) Data sharing statement

The data on the total number of Nurse Practitioners are available in the manuscript. All other

data (e.g. OECD data) are publicly available.

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References

1. Cometto G, Boerma T, Campbell J, Dare L, Evans T. The Third Global Forum: framing the

health workforce agenda for universal health coverage. Lancet Glob Health. 2013;1(6):e324-5.

2. World Health Organization. A Universal Truth: No Health Without a Workforce. Third Global

Forum on Human Resources for Health Report. Global Health Workforce Alliance and World Health

Organization, 2013 November 2013. Report No.

3. Petterson SM, Liaw WR, Tran C, Bazemore AW. Estimating the residency expansion required

to avoid projected primary care physician shortages by 2035. Ann Fam Med. 2015;13(2):107-14.

4. European Commission. Commission Staff Working Document on an Action Plan for the EU

Health Workforce. SWD(2012) 93 final [Internet]. 2012 February 2015. Available from:

http://ec.europa.eu/health/workforce/docs/staff_working_doc_healthcare_workforce_en.pdf.

5. International Council of Nurses. International Council of Nurses: Definition and characteristics

for nurse practitioner/advanced practice nursing roles Geneva2002 [updated October 2014; cited

2015 July]. Available from: https://acnp.org.au/sites/default/files/33/definition_of_apn-np.pdf.

6. World Health Organization. Task shifting to tackle health worker shortages.

WHO/HSS/200703. 2007.

7. World Health Organization. Task shifting: rational redistribution of tasks among health

workforce teams: global recommendations and guidelines. Geneva: World Health Organization,

2008.

8. Stanik-Hutt J, Newhouse RP, White KM, Johantgen M, Bass EB, Zangaro G, et al. The Quality

and Effectiveness of Care Provided by Nurse Practitioners. The Journal for Nurse Practitioners.

2013;9(8):492-500.e13.

9. Martinez-Gonzalez NA, Tandjung R, Djalali S, Huber-Geismann F, Markun S, Rosemann T.

Effects of physician-nurse substitution on clinical parameters: a systematic review and meta-analysis.

PLoS One. 2014;9(2):e89181.

10. Martinez-Gonzalez NA, Djalali S, Tandjung R, Huber-Geismann F, Markun S, Wensing M, et al.

Substitution of physicians by nurses in primary care: a systematic review and meta-analysis. BMC

Health Serv Res. 2014;14:214.

11. Martinez-Gonzalez NA, Rosemann T, Tandjung R, Djalali S. The effect of physician-nurse

substitution in primary care in chronic diseases: a systematic review. Swiss Med Wkly.

2015;145:w14031.

12. Mundinger MO. Advanced-practice nursing--good medicine for physicians? N Engl J Med.

1994;330(3):211-4.

13. Martin-Misener R, Bryant-Lukosius D, Harbman P, Donald F, Kaasalainen S, Carter N, et al.

Education of advanced practice nurses in Canada. Nurs Leadersh (Tor Ont). 2010;23 Spec No

2010:61-84.

14. Gagan MJ, Boyd M, Wysocki K, Williams DJ. The first decade of nurse practitioners in New

Zealand: A survey of an evolving practice. J Am Assoc Nurse Pract. 2014;26(11):612-9.

15. Ter Maten-Speksnijder A, Grypdonck M, Pool A, Meurs P, van Staa AL. A literature review of

the Dutch debate on the nurse practitioner role: efficiency vs. professional development. Int Nurs

Rev. 2014;61(1):44-54.

16. MacLellan L, Higgins I, Levett-Jones T. Medical acceptance of the nurse practitioner role in

Australia: A decade on. J Am Assoc Nurse Pract. 2014(10):2014 Jun 4.

17. Begley C, Elliott N, Lalor J, Coyne I, Higgins A, Comiskey CM. Differences between clinical

specialist and advanced practitioner clinical practice, leadership, and research roles, responsibilities,

and perceived outcomes (the SCAPE study). J Adv Nurs. 2013;69(6):1323-37.

18. NHS Education for Scotland. Advanced Nursing Practice Toolkit. Current issues in

regulation2012 September 2015. Available from:

http://www.advancedpractice.scot.nhs.uk/regulatory-guidance/current-issues-in-regulation.aspx

19. Chamberlain P, Brown CH, Saldana L. Observational measure of implementation progress in

community based settings: the Stages of Implementation Completion (SIC). Implement Sci.

2011;6:116.

Page 21 of 30


BMJ Open

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960

on Novem


http://bmjopen.bm

j.com/

BM



ber 2016. Dow

nloaded from



22

20. Pulcini J, Jelic M, Gul R, Loke AY. An International Survey on Advanced Practice Nursing

Education, Practice, and Regulation. Journal of Nursing Scholarship. 2010;42(1):31-9.

21. Delamaire M-L, Lafortune G. Nurses in advanced roles: A description and evaluation of

experiences in 12 developed countries. OECD Health Working Paper

2010;54(DELSA/HEA/WD/HWP(2010)5).

22. Heale R, Rieck Buckley C. An international perspective of advanced practice nursing

regulation. Int Nurs Rev. 2015;62(3):421-9.

23. Maier CB. The role of governance in implementing task-shifting from physicians to nurses in

advanced roles in Europe, U.S., Canada, New Zealand and Australia. Health Policy.

2015;119(12):1627-35.

24. Carney M. Regulation of advanced nurse practice: its existence and regulatory dimensions

from an international perspective. J Nurs Manag. 2016;24(1):105-14.

25. Freund T, Everett C, Griffiths P, Hudon C, Naccarella L, Laurant M. Skill mix, roles and

remuneration in the primary care workforce: Who are the healthcare professionals in the primary

care teams across the world? Int J Nurs Stud. 2015;52(3):727-43.

26. Spetz J, Fraher E, Li Y, Bates T. How many nurse practitioners provide primary care? It

depends on how you count them. Med Care Res Rev. 2015;72(3):359-75.

27. Hooker RS, Brock DM, Cook ML. Characteristics of nurse practitioners and physician

assistants in the United States. J Am Assoc Nurse Pract. 2015.

28. Kleinpell R, Goolsby MJ. American Academy of Nurse Practitioners National Nurse

Practitioner Sample Survey: Focus on acute care. Journal of the American Academy of Nurse

Practitioners. 2012;24(12):690-4.

29. Doescher MP, Andrilla CHA, Skillman SM, Morgan P, Kaplan L. The Contribution of Physicians,

Physician Assistants, and Nurse Practitioners Toward Rural Primary Care Findings From a 13-State

Survey. Medical Care. 2014;52(6):549-56.

30. Sangster-Gormley E, Martin-Misener R, Downe-Wamboldt B, Dicenso A. Factors affecting

nurse practitioner role implementation in Canadian practice settings: an integrative review. J Adv

Nurs. 2011;67(6):1178-90.

31. Lowe G, Plummer V, Boyd L. Nurse practitioner roles in Australian healthcare settings.

Nursing Management - UK. 2013;20(2):28-35.

32. Richardson G, Maynard A. Fewer doctors? More nurses? A review of the knowledge base of

doctor-nurse substitution. York: Centre for Health Economics, York Health Economics Consortium,

University of York, 1995 Contract No.: 135.

33. Laurant M, Reeves D, Hermens R, Braspenning J, Grol R, Sibbald B. Substitution of doctors by

nurses in primary care. Cochrane Database of Systematic Reviews. 2005(2).

34. OECD Health Statistics. OECD Health Statistics 2015. Definitions, sources and methods.

Metadata. OECD, 2015 November 2015. Report No.

35. Kaiser Family Foundation. Total Number of Nurse Practitioners, by Gender. State Health

Facts: Kaiser Family Foundation; 2015 [cited 2015 August]. Available from: http://kff.org/other/state-

indicator/total-number-of-nurse-practitioners-by-gender/.

36. American Association of Nurse Practitioners. AANP - about us - historical timeline: American

Association of Nurse Practitioners (AANP); 2015 [cited 2015 December]. Available from:

https://www.aanp.org/about-aanp/historical-timeline.

37. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May 2014. 29-1171

Nurse Practitioners. Bureau of Labor Statistics (BLS), 2014.





40. Advisory Committee on Medical Manpower Planning (Capaciteitsorgaan). The 2013

Recommendations for Medical Specialist Training. In the medical, dental, clinical, technological and

mental health areas of training. Utrecht2013 [cited 2015 September]. Available from:

Page 22 of 30


BMJ Open

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960

on Novem


http://bmjopen.bm

j.com/

BM



ber 2016. Dow

nloaded from



23

http://www.capaciteitsorgaan.nl/Portals/0/capaciteitsorgaan/publicaties/Capaciteitsplan%202013/D

EFINITIEF%20hoofdrapport%20engels%20compl.pdf

41. Population Statistics [Internet]. OECD.Stat. 2015 [cited December 2015]. Available from:

http://stats.oecd.org/Index.aspx?DatasetCode=POP_FIVE_HIST.

42. Healthcare Resources: Physicians [Internet]. OECD.Stat. 2015 [cited December 2015].

Available from: http://stats.oecd.org/index.aspx?DataSetCode=HEALTH_STAT.

43. Dutch health professional register (BIG register). Numbers [Cijfers] of health professionals:

Dutch Ministry of Health, Welfare and Sports; 2015 [cited 2015 December]. Available from:

https://www.bigregister.nl/overbigregister/cijfers/.

44. Rowland D. Demographic Methods and Concepts. New York: Oxford University Press; 2003.

45. Reinhardt UE, Hussey PS, Anderson GF. Cross-national comparisons of health systems using

OECD data, 1999. Health Aff (Millwood). 2002;21(3):169-81.

46. Brownson RC, Boehmer TK, Luke DA. Declining rates of physical activity in the United States:

what are the contributors? Annual review of public health. 2005;26:421-43.

47. Anderson GF, Reinhardt UE, Hussey PS, Petrosyan V. It's the prices, stupid: why the United

States is so different from other countries. Health Aff (Millwood). 2003;22(3):89-105.

48. Canadian Institute for Health Information. Regulated Nurses, 2014. Health Workforce

Database: Canadian Institute for Health Information; 2015 [cited 2015 November]. Available from:

https://secure.cihi.ca/estore/productFamily.htm?locale=en&pf=PFC2898&lang=en

49. Nursing and Midwivery Board of Ireland. Statistics. Register statistics 2014 2015 [cited 2015

November]. Available from: http://www.nursingboard.ie/en/statistics.aspx.

50. Nursing and Midwivery Board of Australia. Statistics. 2015 June 2015. Report No.

51. Nursing Council of New Zealand. Annual Report 2015. Wellington, New Zealand: 2015.

52. Dutch Nurse Specialist Registry. Unpublished data on Nurse Specialists (Verpleegkundig

Specialisten), 2009 to 2015, received upon request. 2015.

53. U.S. HRSA National Center for Health Workforce Analysis. Highlights From the 2012 National

Sample Survey of Nurse Practitioners. Rockville, Maryland: U.S. Department of Health and Human

Services, 2014, 2014.

54. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year

ended 31 March 2005. Presented to the Minister of Health pursuant to Section 134 of the Health

Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2005.
















64. OECD. OECD Health Statistics 2015. Definitions, Sources and Methods. Professionally active

physicians. OECD, OECD Health Statistics 2015, 2015.

65. OECD. OECD Health Statistics 2015. Definitions, Sources and Methods. Physicians licensed to

practice OECD, OECD Health Statistics 2015, 2015 July 2015. Report No.

66. Spitzer WO, Sackett DL, Sibley JC, Roberts RS, Gent M, Kergin DJ, et al. The Burlington

randomized trial of the nurse practitioner. N Engl J Med. 1974;290(5):251-6.

Page 23 of 30


BMJ Open

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960

on Novem


http://bmjopen.bm

j.com/

BM



ber 2016. Dow

nloaded from



24

67. Record J. Staffing in Primary Care in 1990: Physician replacement and cost savings. New York:

Springer Publishing Company; 1981.

68. Wijers N, van der Burgt R, Laurant M. Verpleegkundig Specialist biedt kansen.

Onderzoeksrapport naar de inzet van de verpleegkundig specialist op de spoedpost in Eindhoven.

[Specialist Nursing offers opportunities. Research report into the use of the specialist nurse at the

emergency station in Eindhoven]. Nijmegen: IQ healthcare, UMC St Radboud; Eindhoven: KOH

Foundation: 2013.

69. Laurant M. Out of hours primary care. International Innovation 2013 [cited 2015 December].

Available from:

http://rcpsc.medical.org/publicpolicy/imwc/out_of_hours_primary_care_interview_miranda_laurant

.pdf.

70. DiCenso A, Bryant-Lukosius D, Martin-Misener R, Donald F, Abelson J, Bourgeault I, et al.

Factors enabling advanced practice nursing role integration in Canada. Nurs Leadersh (Tor Ont).

2010;23 Spec No 2010:211-38.

71. Australian Government. Health Legislation Amendment (Midwives and Nurse Practitioners)

Act 2010. No. 29, 2010. C2010A00029. 2010.

72. Scanlon A, Cashin A, Bryce J, Kelly JG, Buckely T. The complexities of defining nurse

practitioner scope of practice in the Australian context. Collegian. 2016;23(1):129-42.

73. Minto R. Barriers on nurse practitioner journey. Nurs N Z. 2008;14(6):4.

74. Begley C, Murphy K, Higgins A, Cooney A. Policy-makers' views on impact of specialist and

advanced practitioner roles in Ireland: the SCAPE study. Journal of Nursing Management.

2014;22(4):410-22.

75. Cashin A. Collaborative arrangements for Australian nurse practitioners: A policy analysis.

Journal of the American Association of Nurse Practitioners. 2014;26(10):550-4.

76. Parliament of New Zealand. Misuse of Drugs Amendment Regulations 2014. 2014/199. 2014.

77. van Meersbergen D. Task-shifting in the Netherlands. World Medical Journal (WMA).

2011;57(4):126-30.

78. Phillips SJ. 27th Annual APRN legislative update: advancements continue for APRN practice.

Nurse Pract. 2015;40(1):16-42.

79. Ono T, Lafortune G, Schoenstein M. Health Workforce Planning in OECD Countries: A Review

of 26 Projection Models from 18 Countries. OECD Health Working Papers [Internet]. 2013 October

2015 [cited 2015 October]; No. 62.

80. American College of Physicians. Nurse Practitioners in Primary Care. Philadelphia: American

College of Physicians, 2009.

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Figure 1 and 2:

Figure 1: Total number of NPs and % of professional nursing workforces, 2015*

Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following secondary data

sources: (Canadian Institute for Health Information 2015, Dutch health professional register (BIG register) 2015,

Dutch Nurse Specialist Registry 2015, Kaiser Family Foundation 2015, Nursing and Midwivery Board of

Australia 2015, Nursing and Midwivery Board of Ireland 2015, Nursing Council of New Zealand 2015),






5.6%

1.5%1.3%

0.5%0.3% 0.2%

0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

200000

U.S.: NP

(N=174,943),

PA

Netherlands:

Nurse specialist

(Verpleegkundig

Specialist)

(N=2,749), R

Canada*: NP

(N= 3,560), P

Australia: NP

(N=1,214), R

New Zealand:

NP (N=142), P

Ireland*:

Advanced NPs

(N=141), PA

Total number of NPs NPs % of all RNs (incl NPs)

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Figure 2: Nurse Practitioner density compared to physicians per 100,000 population, 2013*

Sources: Authors’ calculations, based on the following data sources: (U.S. HRSA National Center for Health

Workforce Analysis 2014, Canadian Institute for Health Information 2015, Dutch Nurse Specialist Registry

2015, Kaiser Family Foundation 2015, Nursing and Midwivery Board of Australia 2015, Nursing and

Midwivery Board of Ireland 2015, Nursing Council of New Zealand 2015), Data on physicians based on OECD

2015 database (OECD Statistics 2015)






40.5

12.6 9.8 4.4 3.1 3.1

250

416

255

395

270

304

0.0

50.0

100.0

150.0

200.0

250.0

300.0

350.0

400.0

450.0

U.S.: NPs

(N=127,210), P

Netherlands:

Nurse specialists

(N=2,124), R

Canada: NPs (N=

3,477), PA

Australia: NPs

(N=1,004), R

Ireland: Advanced

NPs (N=141), PA

New Zealand: NPs

(N=142), P

NPs per 100,000 population Physicians per 100,000 (OECD 2015)

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References

Canadian Institute for Health Information. (2015). "Regulated Nurses, 2014. Health Workforce

Database." Retrieved November, 2015, from


Dutch health professional register (BIG register). (2015). "Numbers [Cijfers] of health professionals."

Retrieved December, 2015, from https://www.bigregister.nl/overbigregister/cijfers/.

Dutch Nurse Specialist Registry (2015). Unpublished data on Nurse Specialists (Verpleegkundig

Specialisten), 2009 to 2015, received upon request, Dutch Nurse Specialist Registry

(Registratiecommissie Specialismen Verpleegkunde (RSV)).

Kaiser Family Foundation. (2015). "Total Number of Nurse Practitioners, by Gender. State Health

Facts." Retrieved August, 2015, from http://kff.org/other/state-indicator/total-number-of-nurse-

practitioners-by-gender/.

Nursing and Midwivery Board of Australia (2015). Statistics.

Nursing and Midwivery Board of Ireland. (2015). "Statistics. Register statistics 2014." Retrieved

November, 2015, from http://www.nursingboard.ie/en/statistics.aspx.

Nursing Council of New Zealand (2015). Annual Report 2015. Wellington, New Zealand.

OECD Statistics (2015). Healthcare Resources: Physicians. Paris, OECD.Stat.

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Figure 1 and 2:

Figure 1: Total number of NPs and % of professional nursing workforces, 2015*

Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following data sources:

(Canadian Institute for Health Information 2015, Dutch health professional register (BIG register) 2015, Dutch

Nurse Specialist Registry 2015, Kaiser Family Foundation 2015, Nursing and Midwivery Board of Australia

2015, Nursing and Midwivery Board of Ireland 2015, Nursing Council of New Zealand 2015),






5.6%

1.5%1.3%

0.5%0.3% 0.2%

0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

200000

U.S.: NP

(N=174,943),

PA

Netherlands:

Nurse specialist

(Verpleegkundig

Specialist)

(N=2,749), R

Canada*: NP

(N= 3,560), P

Australia: NP

(N=1,214), R

New Zealand:

NP (N=142), P

Ireland*:

Advanced NPs

(N=141), PA

Total number of NPs NPs % of all RNs (incl NPs)

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Figure 2: Nurse Practitioner density compared to physicians per 100,000 population, 2013*

Sources: Authors’ calculations, based on the following data sources: (U.S. HRSA National Center for Health

Workforce Analysis 2014, Canadian Institute for Health Information 2015, Dutch Nurse Specialist Registry

2015, Kaiser Family Foundation 2015, Nursing and Midwivery Board of Australia 2015, Nursing and

Midwivery Board of Ireland 2015, Nursing Council of New Zealand 2015), Data on physicians based on OECD

2015 database (OECD Statistics 2015)






40.5

12.6 9.8 4.4 3.1 3.1

250

416

255

395

270

304

0.0

50.0

100.0

150.0

200.0

250.0

300.0

350.0

400.0

450.0

U.S.: NPs

(N=127,210), P

Netherlands:

Nurse specialists

(N=2,124), R

Canada: NPs (N=

3,477), PA

Australia: NPs

(N=1,004), R

Ireland: Advanced

NPs (N=141), PA

New Zealand: NPs

(N=142), P

NPs per 100,000 population Physicians per 100,000 (OECD 2015)

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REFERENCES

Canadian Institute for Health Information. (2015). "Regulated Nurses, 2014. Health Workforce

timhttps://secure.cihi.ca/estore/productFamily.htm?locale=en&pf=PFC2898&lang=en

Dutch health professional register (BIG register). (2015). "Numbers [Cijfers] of health professionals."

Retrieved December, 2015, from https://www.bigregister.nl/overbigregister/cijfers/.

Dutch Nurse Specialist Registry (2015). Unpublished data on Nurse Specialists (Verpleegkundig

Specialisten), 2009 to 2015, received upon request, Dutch Nurse Specialist Registry

(Registratiecommissie Specialismen Verpleegkunde (RSV)).

Kaiser Family Foundation. (2015). "Total Number of Nurse Practitioners, by Gender. State Health

Facts." Retrieved August, 2015, from http://kff.org/other/state-indicator/total-number-of-nurse-

practitioners-by-gender/.

Nursing and Midwivery Board of Australia (2015). Statistics.

Nursing and Midwivery Board of Ireland. (2015). "Statistics. Register statistics 2014." Retrieved

November, 2015, from http://www.nursingboard.ie/en/statistics.aspx.

Nursing Council of New Zealand (2015). Annual Report 2015. Wellington, New Zealand.

OECD Statistics (2015). Healthcare Resources: Physicians. Paris, OECD.Stat.

U.S. HRSA National Center for Health Workforce Analysis (2014). Highlights From the 2012 National

Sample Survey of Nurse Practitioners. Rockville, Maryland, U.S. Department of Health and Human

Services, 2014.

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A descriptive, cross-country analysis of the nurse practitioner workforce in six countries: size, growth,

physician substitution potential

Journal: BMJ Open

Manuscript ID bmjopen-2016-011901.R1

Article Type: Research

Date Submitted by the Author: 10-Jul-2016

Complete List of Authors: Maier, Claudia; University of Pennsylvania, Center for Health Outcomes and Policy Research, School of Nursing; Technische Universitat Berlin, Department of Healthcare Management

Barnes, Hilary; University of Pennsylvania, Center for Health Outcomes and Policy Research, School of Nursing Aiken, Linda; University of Pennslvania, Center for Health Outcomes and Policy Research, School of Nursing Busse, Reinhard; Technische Universität Berlin, Department of Health Care Management

<b>Primary Subject Heading</b>:

Nursing

Secondary Subject Heading: Global health

Keywords: nursing, health workforce, physicians, PRIMARY CARE, nurse practitioner


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A descriptive, cross-country analysis of the nurse practitioner workforce in six

countries: size, growth, physician substitution potential

Corresponding author: Claudia B Maiera) b), MSc

a) Harkness & B. Braun Fellow in Healthcare Policy and Practice


University of Pennsylvania, School of Nursing

Claire Fagin Hall

418 Curie Blvd

Philadelphia, PA 19104-4217; b) Department of Healthcare Management,

Technische Universität Berlin, Germany




Phone: +49 176 32944628

Fax: +49 30 314 28433

[email protected]

[email protected]

Hilary Barnes, PhD, CRNP

Postdoctoral Research Fellow



418 Curie Blvd



Phone: +1 215-898-4908

Fax: +1 215-573-2062

[email protected]

Linda H Aiken, PhD, RN

Claire M Fagin Professor and Director



418 Curie Blvd



Phone: +1 215-898-9759

Fax: + 215-573-2062

[email protected]

Reinhard Busse, PhD, MD, MPH, FFPH

Head of the Department of Health Care Management

Faculty of Economics and Management

Head of the Berlin hub of the European Health Observatory on Health Systems and Policies

Technische Universität Berlin


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Phone: +49 30 314 28420

Fax: +49 30 314 28433

[email protected]

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ABSTRACT

Objectives. Many countries are facing provider shortages and imbalances in primary care or

are projecting shortfalls for the future, triggered by the rise in chronic diseases and

multimorbidity. In order to assess the potential of Nurse Practitioners (NP) in expanding

access, we analysed the size, annual growth (2005-2015), and the extent of advanced practice

of NPs in six Organisation for Economic Cooperation and Development (OECD) countries.

Design. Cross-country data analysis of national nursing registries, regulatory bodies,

statistical offices data; as well as OECD health workforce and population data, plus literature

scoping review.

Setting/Participants. NP and physician workforces in six OECD countries (Australia,

Canada, Ireland, Netherlands, New Zealand, United States).

Primary and secondary outcome measures. The main outcomes were the absolute and

relative number of NPs per 100,000 population compared to the nursing and physician

workforces; the Compound Annual Growth Rates (CAGR), annual and median percentage

change from 2005-2015; and a synthesis of the literature on the extent of advanced clinical

practice measured by physician substitution effect.

Results. The United States showed the highest absolute number of NPs and rate per

population (40.5 per 100,000 population), followed by the Netherlands and Canada (12.6 and

9.8), Australia (4.4), and Ireland and New Zealand (3.1, respectively). Annual growth rates

were high in all countries, ranging from annual compound rates of 6.1% in the United States

to 27.8% in the Netherlands. Growth rates were between three- and nine-times higher

compared to physicians. Finally, the empirical studies emanating from the literature scoping

reviews suggested that NPs are able to provide 67-93% of all primary care services, yet, based

on limited evidence.

Conclusions. NPs are a rapidly growing workforce with high levels of advanced practice

potential in primary care. Workforce monitoring based on accurate data is critical to inform

educational capacity and workforce planning.

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Strengths and limitations of this study

• This study determines the total and relative size of Nurse Practitioners per 100,000

population and growth rates in comparison to physicians in six OECD countries.

• A strength of this study is the analysis of comprehensive and largely unexplored data

from authoritative sources in the six countries.

• Annual growth rates were calculated for 2005-2015 using compound annual growth

rates (CAGR), annual; and median percentage change to account for excessive yearly

changes found.

• The study faces limitations as to accuracy of data, data variability of the activity levels

of NPs and physicians, yet, for within-country comparisons, we used consistently the

same activity levels for NPs and physicians.

• The few empirical studies on the substitution effect of NPs for physicians show that

NPs can work at high levels of advanced practice, however, future research is

necessary to validate the findings.

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BACKGROUND

Health workforce shortages and geographical imbalances exist in many countries worldwide

(1). The need for primary care providers is increasing in response to the intensifying

healthcare needs of their populations, triggered by the increasing rates of patients with chronic

conditions and multimorbidity (2, 3). While educating more physicians is one workforce

strategy, countries are also investing increasingly in a highly qualified nursing workforce,

such as Nurse Practitioners and other Advanced Practice Nurses (NP/APN), with usually

Master’s level education (4). Expanding the roles of nurses combined with task-shifting from

physicians to nurses as suggested by the World Health Organization, has received policy

attention to respond to shortages, long waiting times and high care needs of patients with

chronic conditions (5, 6).

There is a consistent body of evidence showing that nurses with advanced education can

provide high-quality care that is comparable to physicians for a range of acute and chronic

illnesses (7-10). The U.S. was the first country to introduce NPs in 1965 (in Colorado),

followed by Canada in 1967 (in Nova Scotia) (11, 12). NP practice regulations have since

been instituted and managed at the subnational level in these countries. Other countries have

more recently introduced NPs, including the United Kingdom (U.K.), Ireland, the

Netherlands, Australia and New Zealand (13-17).

The extent to which NPs are effective in addressing shortages and the intensifying care needs

of patients with chronic conditions depends on the scale of this workforce, and its integration

and implementation in healthcare (18). Scale in this context refers to two factors, sufficient

numbers of NPs and their extent of advanced practice. Both elements are critical to assess the

contribution of the workforce.

Existing international research on the size of the NP workforce is limited. The international

literature has compared primarily NP education, governance, and regulation of titles (19-23).

In an overview of the primary care workforce in six countries, the total number of NPs was

found to be low in most countries (24). However, the study only provided the total number of

providers, no further information on its relative size compared to other professions or time

trends. A 2010 OECD report found the NP workforce to be the largest in the U.S. in absolute

and relative size compared to the total nursing workforce, followed by Canada, Australia and

Ireland (20). Yet, the report did not differentiate between activity levels and dates back to

2010. It did not provide data on time trends. At the individual country-levels, many studies

exist, particularly in the U.S. that aim to quantify the total number of NPs, by employment,

specialty and clinical practice area (25-28). They found that the various data sources provide a

patchy overview in the U.S., particularly when focusing on the clinically active NPs and

specific specialty areas (25). The comparatively fewer studies analysing the size of NPs in

Canada, Australia, and New Zealand found that the workforce is small, but provided limited

information beyond the number of providers (29, 30).

While NPs perform a substantially expanded range of clinical services, there is limited

knowledge on the detailed level of advanced practice. The 2010 OECD report provides

information on the typical tasks and activities provided by NPs in Australia, Canada, Ireland,

the United Kingdom and the U.S. suggesting that NPs provide a large range of services at the

interface with the medical profession (20). Conceptually, the substitution effect of physicians

by NPs refers to the quantification of how many patients or services in a particular care

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setting can be performed by NPs that are usually provided by physicians (31, 32). In a

systematic review, 30-70% of clinical activities of physicians were found could be taken over

by NPs or other non-physician providers, however, most of the included studies were

conducted in the 1970s and 1980s and included a wide range of non-physician providers,

including NPs, other nursing roles and physician assistants (31). NPs’ roles have expanded

internationally, hence a review focused on NPs only, providing an update of the literature, is

relevant to synthesise the evidence on the extent of advanced practice and variations across

countries.

This study pursued the following three research objectives: 1) to analyse the absolute and

relative size of the NP workforce in six OECD countries (Australia, Canada, Ireland, the

Netherlands, New Zealand, and the U.S.), focusing on practicing NPs, their proportion of the

total nursing workforce and rates per 100,000 population relative to the physician workforce;

2) to examine time trends from 2005-2015 in the NP compared to the physician workforces;

and 3) to synthesise the evidence on the extent of advanced practice in primary care referred

to as physician ‘substitution effect’.

The three objectives are separate, but interrelated: all three parameters (size, growth, percent

of physician substitution) are critical for workforce planning and projections (33). Data on the

three parameters provide the numerical basis in order to forecast the current and future

potential of NPs in addressing the expected growing demand and intensifying healthcare

needs.

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METHODS

Definitions and outcome measures

In order to assess the absolute and relative size of the NP workforce, we followed the OECD

definition of activity levels of health professions: (i) practicing professionals (providing direct

patient care), (ii) professionally active (providing direct patient care, plus working in related

administration, management or research as part of the profession), and (iii) registered/licensed

to practice (authorised to practice, including practicing, professionally active and non-

practicing providers) (34). For this study, the activity status practicing NPs was preferred over

professionally active and registered/licensed, following the OECD (34). In countries with no

available information on the number of practicing NPs, data on professionally active or

registered was used.

To analyse time trends, we compared the yearly growth rates of NPs to physicians from 2005

to 2015 where available. We chose the physician profession as comparator for two reasons.

First, to compare the growth rates to estimate the potential in alleviating shortages and

expanding capacity and second, since OECD data on time trends are of better quality and

comparability than those for the nursing profession.

To analyse the research objective on NPs levels of advanced practice, we performed a

literature scoping review (35), focusing on a concept referred to as ‘substitution effect’, which

estimates the potential of a new, extended professional role in taking up activities of an

established profession (31).

First phase: identification of countries and data availability - the TaskShift2Nurses

Study

We identified countries with NP/APNs based on an expert survey in 39 industrialised

countries (Task-Shift2Nurses Study, 2015). Information on the survey itself, its sampling

strategy, data collection and analysis is provided elsewhere (22, 36). A total of 93 country

experts participated (response rate 85.3%). The survey included questions on scope of

practice and education, data availability, existence of nursing registries, and mandatory vs.

voluntary registration policies, among others. Institutional Review Board (IRB) approval was

obtained at the University of Pennsylvania.

The TaskShift2Nurses study identified eleven countries with NP/APNs: Australia, Canada,

Finland, Ireland, Netherlands, England, Northern Ireland, Scotland, Wales, New Zealand and

the U.S (22, 36). Definitions used were existence of NP/APNs, education at NP/APN level

and advanced practice focusing on primary care, measured by seven clinical activities:

authority to prescribe medications, order medical tests, decide on medical treatment,

diagnose/perform advanced health assessment, referrals, responsibility for a panel of patients,

and first point of contact (4). The survey was integral to this study insofar, as it helped

identify countries with data on NP/APN and the respective authoritative sources.

For the purpose of this study, in a subsequent step we contacted country experts individually

to obtain further information on data sources and holders. Finland and the countries within the

United Kingdom were excluded from this study, because no registry data or other

national/federal or subnational data sources on NP/APNs were identified.

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Second phase: country-specific secondary data collection

In a subsequent step, we retrieved secondary data on NPs for the remaining six countries from

authoritative sources as advised by country experts. All six countries had NP or similar roles

working in advanced practice, of which the titles were regulated and registration was

mandatory. The secondary data collection phase took place between August 2015 and January

2016. These sources included nursing boards or councils (Australia, Ireland, New Zealand),

an institute on health information (Canada), and a nurse specialist registry

(Registratiecommissie Specialismen Verpleegkunde, RSV) in the Netherlands. In the

Netherlands, Nurse Specialists (Verpleegkundig Specialisten) are sometimes referred to as

NPs in English literature (14), however, we decided to keep the translation closest to its

original title, since this title is regulated.

In the U.S., several data sources were reviewed, including data from the Kaiser Family

Foundation (KFF) (37), American Association of Nurse Practitioners (AANP) (38), and the

U.S. Bureau of Labor Statistics (39-41). Challenges of the U.S. data include the co-existence

of multiple sources which calculate the workforce differently. The KFF provided data on

professionally active NPs based on active state NP licenses, however, no data on time trends

were available. The AANP data cover NPs licensed to practice; however, these data are

estimated and actual numbers not available to the public. The U.S. Bureau of Labor Statistics

estimates the professionally active NP workforce, but NP-specific data are only available

since 2012 and exclude self-employed NPs (39-41). To analyse the first research objective,

we chose the data source based on the year of data availability (2015), the completeness of the

data as to the total size of the workforce, and the activity status (data covering ‘practising”

NPs, followed by professionally active and registered/licensed). For the second research

objective, we prioritised on data sources with time series (ideally from 2005 to 2015 or

longest period covered).

Time series data was limited in four countries, the U.S., the Netherlands, Ireland and

Australia. Canada and New Zealand were the only two countries with continuous data on time

series available since 2005, whereas the Netherlands had data since 2009, the year of

introduction of the specialist registry, Ireland since 2010 and Australia since 2012.

Third phase: literature scoping review on the extent of advanced practice

In addition to the secondary data analysis, we conducted a comprehensive literature scoping

review (35), covering Medline, CINAHL, Google Scholar, and grey literature, to identify

studies on substitution effect/extent of advanced practice. Literature scoping reviews have

evolved over the last 20 years as a method for synthesising the evidence on a specific topic or

research question (35, 42). Compared to systematic literature reviews, research questions in

scoping reviews are broader and typically defined per PCC (Population, Concept, Context)

instead of PICO (Participants, Interventions, Comparisons, Outcomes) elements (35), hence,

suitable to a broader research question (see Supplement). Moreover, scoping reviews are

designed to provide a synthesis of a wider and broader type of evidence beyond peer-

reviewed journal articles, and include various, heterogeneous sources instead of focusing on

the best evidence only (43). We followed the methodology by the Joanna Briggs Institute (35)

(see Supplement). Studies were included if they quantified the extent of advanced practice,

also referred to as physician “substitution effect”. We included all evidence that measured

either the percentage of typical physician-provided activities that can be performed by NPs in

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primary care or the percentage of all services that can be provided by NPs (31, 33). Search

terms included various combinations of the terms substitution, nurse practitioner, primary

care, among others (see Supplement). The search was conducted in English, plus we

contacted country experts for additional, grey literature.

Data analysis

Regarding research objective 1, we calculated NP rates per 100,000 population using the

population sizes provided by the OECD 2015 population statistics online database (44). To

compare the density of NPs with physicians, we retrieved the physician ratios per 1,000 from

the OECD database, which we subsequently multiplied by 100 to obtain rates per 100,000

population (45). Data on the nursing workforce was retrieved from the same data holders from

which the data on NPs were obtained, except for the Netherlands where nurse specialists are

registered in a separate registry (46).

As for research objective 2 on time trends, we calculated the yearly percentage change of NPs

and physicians (e.g. 2005-06, 2006-07), covering 2005 to 2015 or years available, to assess

the relative growth of the NP profession compared to the physician profession. Percentage

change is a common arithmetic method, used in many disciplines including demographics

(47). It is based on the calculation of the absolute difference at two points in time and divided

by the original group size, multiplied by 100. This method allows to quantify the increase or

decrease over time periods irrespective of groups’ differences in size. In addition to yearly

percentage changes, we calculated the Compound Annual Growth Rates (CAGR) which is

commonly used in comparison of time trends (48-50), since it smoothes yearly growth rates

over time. In addition, we calculated the average and median percentage change across the

entire time period for each of the country and profession covered (34).

Regarding research objective 3, all studies identified from the literature scoping review were

reviewed according to inclusion and exclusion criteria (see Supplement). Studies were

included if they quantified the extent of substitution effect in primary care, provided the study

was implemented in one of the six countries. We subsequently extracted the numerical results

of the percentage of all services that NPs were able to provide, and information on the study

design, participants, country and service delivery contexts.

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RESULTS

Total and relative size of the Nurse Practitioner workforce

The United States showed the largest number of professionally active NPs (N= 174,943)

compared to the other five OECD countries, which represented 5.6% of its total active U.S.

nursing workforce in 2015 (37) (Figure 1). In the Netherlands and Canada, both the total and

relative size was lower, percentages were 1.5% and 1.3% respectively, based on data on

registered NPs in the Netherlands and practicing NPs in Canada. In Australia, New Zealand

and Ireland, the relative sizes were very small, 0.5% and less.

[Figure 1: Total number of NPs and % of professional nursing workforces, 2015*]

Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following data sources: (37,

46, 51-55),






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Results regarding the workforce density per population showed similar patterns across the six

countries (Figure 2). The rate of NPs in the United States was highest, at 40.5 practicing NPs

per 100,000 population (44, 56) based on 2012 data to allow for comparisons with physicians.

NPs were less than one fifth of the U.S. physician workforce (44, 45).

In the Netherlands and Canada, rates were considerably lower compared to the U.S. at 12.6

and 9.8 per 100,000 population. Compared to physicians, Australia, Ireland and New Zealand

showed very low rates.

[Figure 2: Nurse Practitioner density compared to physicians per 100,000 population, 2013*]

Sources: Authors’ calculations, based on the following data sources: (37, 51-56), Data on physicians based on

the OECD 2015 database (45), drawn from the following primary data sources: United States: American Medical Association (AMA); Canada: Canadian Institute for Health Information (CIHI); Netherlands: The BIG register, Australia:

Australian Institute of Health and Welfare (AIHW), New Zealand: Medical Council Medical Register (57, 58).






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Growth of the Nurse Practitioner workforce from 2005-2015

All countries showed a continuous growth of their NP workforce from 2005 to 2015 or those

years available (Table 1). However, growth rates varied considerably across countries; and

within countries between NPs and physicians.

In the U.S., NPs licensed to practice increased from an estimated 106,000 in 2004 to 192,000

in 2014 (38). Rates per 100,000 population increased from 35.87 to 60.22 NPs per 100,000

population. Data on professionally active NPs showed an increase from 105,780 to 122,050

NPs, yet were only available from 2012 to 2014 (39-41).

In the Netherlands, the numbers of Nurse Specialists registered increased rapidly, from 140 in

2009 to 2,749 in 2015. The rate of Nurse Specialists per 100,000 population in the

Netherlands showed the most rapid increase of all countries studied, more than 14-fold, from

0.85 Nurse Specialists in 2009 to 14.74 Nurse Specialists per 100,000 in 2014.

In Canada, the rate of NPs per 100,000 increased from 2.9 in 2005 to 10.7 in 2014, more than

three-fold. In Australia, the NP rate grew from 3.5 in 2012 to 5 per 100,000 population in

2014. Although a rapid increase took place in New Zealand from 0.3 in 2005 to 3.1 in 2014,

and in Ireland from 0.8 in 2010 to 3.1 in 2014, total numbers remained at low levels.

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Nurse Practitioner compared to physician growth rates

We present compound annual growth rates (CAGR), and the median percentage changes over

the 2005-2015 period to show differences in the calculation methods (table 2). In order to

account for the extremly high growth rates in the first year in the Netherlands and Ireland due

to the small numbers (Netherlands: 2009-10, Ireland: 2010-11), we calculated the CAGR for

the full period and the CAGR without the first year for the two countries.

Growth among NPs was high in all countries, and consistently and considerably higher than

among physicians. The compound growth rate among Nurse Specialists in the Netherlands

was 27.8% (CAGR 2010-2015), the highest of all six countries. The yearly growth was higher

than that of its medical workforce at 2.9%, overall yearly growth was more than 9-times

higher. In New Zealand and Canada, compound annual growth of NPs was 27.3% and 16.7%

respectively, approximately nine- and five-times higher than that of their medical workforces

(2.8%, and 3.3%). Ireland showed a comparatively lower yearly increase of its NP workforce,

yet, still a more than four-times growth compared to its physician workforce. Of the six

countries, the United States had the lowest annual compound growth of 6.1% or 7.4%

annually depending on the data sources, yet, was still more than three-times higher than that

of physicians (38-41, 44, 45).

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Table 1: Total number of Nurse Practitioners and Physicians, six countries, 2005-2015 (or years available)

Sources: authors’ calculations, based on the following data sources (38-41, 45, 51-55, 59-68), The OECD statistics on physicians are based on the following primary data sources: United States:

American Medical Association (AMA); Canada: Canadian Institute for Health Information (CIHI); Netherlands: The BIG register, Australia: Australian Institute of Health and Welfare (AIHW),

New Zealand: Medical Council Medical Register (57, 58).

Notes: NP=Nurse Practitioners, NS=Nurse Specialists, MD=Medical Doctors/Physicians, P=Practicing, PA=Professionally Active, R=Registered, ..= not available, Caveats: United States: *data on

professionally active Nurse Practitioners do not include self-employed, hence underestimate totals (39), ^year 2004 (in lieu of 2005 data availability) e= data on registered NPs are estimates, exact

numbers are not publicly available (38), Netherlands: Data on nurse specialists (NS, R) include approximately 10 invalid cases per year used as test accounts (range 8-12) in the database that cannot

be filtered out (estimated 8 cases yearly in 2009/2010/2011/2012 and 12 in 2013/2014/2015) (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January

2016), Canada: OECD data on MDs, based on two combined data sources, which may overstate the number of physicians, since interns and residents may be registered twice, Australia: break in OECD time series data on MDs in 2010, due to change of data holders. (57, 58)



PA R R PA PA R R R R R R PA PA

2005 .. 106,000e^ 902,053 943 69,619 .. 55,673 .. 67,890 14 11,555 .. ..

2006 .. .. 921,904 1,129 70,870 .. 57,098 .. 71,740 21 11,889 .. 11,617

2007 .. 120,000e 941,304 1,344 72,903 .. 58,661 .. 77,193 30 12,318 .. 12,311

2008 .. .. 954,224 1,626 75,155 .. 60,300 .. 78,909 46 12,746 .. 13,022

2009 .. 130,000e 972,376 1,990 78,623 140 62,057 .. 82,895 50 13,176 .. 13,663

2010 .. 140,000e 985,375 2,486 80,895 807 63,585 .. .. 72 13,398 38 14,029

2011 .. 148,000e 1,004,635 2,777 84,313 1,272 65,568 .. 87,790 91 14,021 97 14,814

2012 105,780* 157,000e 1,026,788 3,157 87,306 1,847 68,119 788 91,504 103 14,280 109 14,498

2013 113,370* 171,000e 1,045,910 3,477 90,205 2,124 69,942 1,004 91,467 117 14,596 123 14,054

2014 122,050* 192,000e .. 3,786 .. 2,480 .. 1,165 .. 138 14,787 141 14,016

2015 .. .. .. .. .. 2,749 .. 1,214 .. 157 .. .. ..

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Table 2: Annual growth of the nurse practitioner and physician workforces, measured by yearly percentage change (%), median percentage change

and Compound Annual Growth Rate (CAGR, %), in six countries, 2005-2015 (or years available)

Sources: authors’ calculations, based on the following data sources (38-41, 45, 51-55, 59-68). The OECD statistics on physicians are based on the following primary data sources: United States: American Medical Association (AMA); Canada: Canadian Institute for Health Information (CIHI); Netherlands: The BIG register, Australia: Australian Institute of Health and Welfare (AIHW),

New Zealand: Medical Council Medical Register (57, 58).

Notes: CAGR=Compound Annual Growth Rate, [1]=CAGR (2004/2014) calculated based on 2004-2014 data (2004 data used in lieu of missing 2005 data) [2]=CAGR (2010-2015), 2009-10 was

excluded due to excessive growth rate caused by small numbers (CAGR 2009-2015: 64.3%, not shown), [3]=CAGR (2011-2014), 2010-11 data excluded (CAGR 2010-14: 38.8%, not shown),

PC=Percentage Change, NP=Nurse Practitioners, NS=Nurse Specialists, MD=Medical Doctors/Physicians, P=Practicing, PA=Professionally Active, R=Registered, ..= not available, Caveats:

United States: *data on professionally active Nurse Practitioners do not include self-employed (39). °Data on registered NPs are estimates, exact numbers are not publicly available (38),

Netherlands: Data on nurse specialists (NS, R) include approximately 10 invalid cases per year used as test accounts (range 8-12) in the database that cannot be filtered out (estimated 8 cases yearly

in 2009/2010/2011/2012 and 12 in 2013/2014/2015) (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January 2016), Canada: OECD data on MDs,

based on two combined data sources, which may overstate the number of physicians, since interns and residents may be registered twice, Australia: break in OECD time series data on MDs in 2010,

due to change of data holders. (57, 58)



PA* R° R PA PA R R R R R R PA PA

2005-2006 .. ..^ 2.2% 19.7% 1.8% .. 2.6% .. 5.7% 50.0% 2.9% .. ..

2006-2007 .. .. 2.1% 19.0% 2.9% .. 2.7% .. 7.6% 42.9% 3.6% .. 6.0%

2007-2008 .. ..^ 1.4% 21.0% 3.1% .. 2.8% .. 2.2% 53.3% 3.5% .. 5.8%

2008-2009 .. .. 1.9% 22.4% 4.6% .. 2.9% .. 5.1% 8.7% 3.4% .. 4.9%

2009-2010 .. 7.7% 1.3% 24.9% 2.9% 476.4% 2.5% .. .. 44.0% 1.7% .. 2.7%

2010-2011 .. 5.7% 2.0% 11.7% 4.2% 57.6% 3.1% .. .. 26.4% 4.6% 155.3% 5.6%

2011-2012 .. 6.1% 2.2% 13.7% 3.5% 45.2% 3.9% .. 4.2% 13.2% 1.8% 12.4% -2.1%

2012-2013 7.2% 8.9% 1.9% 10.1% 3.3% 15.0% 2.7% 27.4% 0% 13.6% 2.2% 12.8% -3.1%

2013-2014 7.7% 12.3 .. 8.9% .. 16.8% .. 16.0% .. 17.9% 1.3% 14.6% -0.3%

2014-2015 .. .. .. .. .. 10.9% .. 4.2% .. 13.8% .. .. ..

Median PC 7.5% 7.7% 2% 19.0% 3.2% 30.1% 2.8% 16.0% 4.6% 22.2% 2.9% 13.7% 3.8%

CAGR 7.4% 6.1%[1] 1.9% 16.7% 3.3% 27.8%[2] 2.9% 15.5% 3.8% 27.3% 2.8% 13.3%[3] 2.4%

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Extent of advanced clinical practice

The scoping review yielded a total of 1,022 results. After removal of 31 duplicates, the titles

of 991 records were screened and the full-text of 46 studies analysed according to the

inclusion/exclusion criteria (see Supplement for additional information). The review resulted

in five results, together reporting the findings from three empirical studies, quantifying the

extent of clinical practice of NPs compared to physicians in primary care. These were

conducted in the U.S., Canada and the Netherlands (Table 3). No studies conducted in the

three other countries were identified. The five studies found NPs able to provide between 67%

and 93% of primary care services, emanating from one Randomised Controlled Trial (RCT)

conducted in Canada (69), one quasi-experimental study in the Netherlands (70-72), and one

survey to physicians and NPs in the U.S. (28) (see Supplement). The findings were based on

small sample sizes, did not differentiate between specialty areas of NPs, covered different

practice areas within primary care, such as rural areas in the U.S. (28) or out-of-hours services

in the Netherlands. Moreover, the RCT in Canada was conducted more than 40 years ago

(69).

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Table 3: Level of advanced clinical practice, measured by physician “substitution effect” of nurse practitioners

Country Study design

(Years) Setting Participants Results Referen

ce

Canada RCT to assess the

effects of substituting NPs

for physicians in

primary care (1971-1972).

Two suburban

Ontario family practices

Total patient N = 1,598

families (4,325 individuals) of which 529

families (1,398

individuals) were randomized to each

physician; 270 families

(765 individuals) were

randomized to each NP

67% of all primary care patient visits can be provided by NPs.

Care delivery was similar between physicians and NPs. There were no

statistically significant differences between patients seen by NPs compared

to patients seen by physicians in patient functional capacity, indexes of social and emotional function, mortality, or satisfaction with care.

(69)

Netherlands Quasi-experimental

study to compare the number of

patients and

caseloads between NPs and GPs in

out-of-hours

services (2011 to 2012)

Out-of-hours

primary care

Intervention: one NP and

four GPs, control: five GPs working in out-of-

hours services. Total

patient N=12,092 from one GP cooperative

extracted from medical

records

More than 77% of patients fit the scope-of-practice of Nurse Practitioners

(Verpleegkundig Specialist) in out-of-hours care. On average 16.3% of all patients were treated by NPs, whereas 20.9% of

patients were treated by GPs.

75-83% of clinical activities in out-of-hours primary care settings (weekend

shifts in GP practices) could be taken over by Nurse Specialists

(Verpleegkundig Specialist)

(70)

(71, 72)

U.S. Self-report, mailed survey to a random

sample of 4,000

physicians and

3,000 NPs with

rural addresses (all

specialties)

Rural primary care in 13

states with at

least 2 from

each U.S.

Census

Region (4

regions).

Final sample included

788 primary care

physicians (response

rate: 25%); and 918

primary care NPs (40%)

75-93% of weekly primary care outpatient visits can be provided by NPs.a

In the outpatient setting, primary care clinical activitiesb were comparable

between physicians and NPs in the outpatient setting.

(28)

Source: see directly in the table, see Supplement for more details

Notes: NP = nurse practitioners; RCT = randomised controlled trial; GP = general practitioner a In an unadjusted regression model, NP average weekly number of outpatient visits was 75% of physician volume. In an adjusted model (age, sex, geographic location, and

practice setting), NP average weekly number of outpatient visits was 93% of physician volume. b On average, physicians conducted more well-child visits than NPs (12.6 vs. 7.4, p <0.001). Differences for prenatal visits and minor procedures were non-significant.

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DISCUSSION

The size of the NP workforce in the six countries studied is variable, but growing rapidly,

with high levels of practice in primary care, yet based on limited evidence. The U.S. is the

only country where the NP workforce has reached a considerable density of approximately

40.5 practicing NPs per 100,000 population, in other countries the workforce is smaller,

ranging from 12.6 per 100,000 population in the Netherlands to low levels in New Zealand

and Ireland. Yet, the workforce has rapidly and consistently grown since 2005 in all countries,

at much higher rates than the physician workforce. Moreover, the few existing empirical

studies show the potentially large and wide range of advanced clinical activities that NPs can

provide. The studies suggest that between 67 and 93% of primary care visits and services can

be safely provided by NPs. Taken together, the findings indicate that the NP workforce holds

future promise in filling unmet care needs in primary care.

The study faces several limitations. First, data sources varied in the activity levels covered,

e.g. practicing, professionally active or registered NPs and physicians across countries. This

limitation is faced by all international data on health workforces, including the OECD and

WHO, since countries use different registration policies and data collection methodologies.

However, for within-country comparisons, we consistently compared the same activity levels

of NPs and physicians. Second, we took the OECD data on physicians at face value; however,

among the underlying primary data sources, differences may exist in terms of accuracy and

validity. Future research could compare the accuracy of the OECD data with individual

national/subnational primary data sources. Third, due to the U.S. decentralised approach of

licensing NPs, several different data sources and holders were identified. Large differences

exist across data sources in terms of size, and activity levels, limiting overall quality of data.

Additionally, state-level authority over NP licensing may lead to double counting NPs who

hold licenses in multiple states. Moreover, data on time trends of ten years were based on

estimates and covered the licensed workforce. Hence, the U.S. data can at best be

approximations to the actual number of practicing NPs over the ten-year period and therefore

need to be interpreted in light of the limitations.

Our results are largely in line with previous international research showing the relatively

small scale of the NP workforce (20, 24). Reasons for the differences between the scale of the

NP workforce in the U.S. and other countries have not been empirically validated. It is

assumed they may be multifactorial. Not only the years of existence may play a role, as the

U.S. was the first country to implement NPs in 1965 (in the earliest adopting state), but other

factors may also influence their size and growth. Canada (Nova Scotia) introduced the first

NPs only two years later, but relies on a much lower total number and density of NPs than the

U.S.. Reasons for a small NP base in Canada have been discussed, and include limited role

clarity, differences across provinces and territories in education and uptake, and challenges in

creating positions for NPs (12, 29, 73). Moreover, large variations in the NP density exist

across provinces and territories, rural versus urban areas and by employer, suggesting a more

granular analysis of potentially influencing policies and other factors may be needed (51). The

low numbers in the Netherlands, Australia, and particularly in New Zealand and Ireland are at

least partly influenced by the fact that NPs were introduced much later in these countries

(1990s and 2000s) than in the U.S. and Canada (13, 24, 61, 74-76).

Time series data showed a considerable increase of NPs in all countries studied, much higher

yearly growth than found in the medical workforces. This trend may partially but not entirely

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be related to the fact that increases in very small numbers result in large growth rates. We

took account of this by excluding extreme values from the CAGR calculations for Ireland and

the Netherlands, and calculated median percentage changes which were comparable to

CAGR.

The continuous and higher growth rates point to an emerging NP workforce that may not have

reached its full numerical potential, as compared to professions with a longer tradition, such

as the physician workforce. Many countries in our study have removed or eased regulatory

barriers to expanded NP scope of practice, such as Australia, Canada, New Zealand, the

Netherlands and the U.S. (77-81). Canada and New Zealand expanded prescriptive authority

for NPs in 2012 and 2014, respectively (78, 82). In Australia, NPs got access to the Medical

and Pharmaceutical Benefits Scheme in 2010, easing their practice, the Netherlands has

regulated the Nurse Specialist profession in 2009 and expanded scope of practice in 2011,

entering into effect in 2012 (79, 83). In the U.S., an increasing number of states have removed

regulatory barriers by revising scope of practice laws over the last decade (80, 84) . Future

research is warranted to identify systemic facilitators and barriers that may cause variations in

the implementation of NP roles in different country contexts.

Moreover, medical student intake or residency places are restricted by some sort of quota

system or numerus clausus in all countries, to avoid an excessive medical workforce and at

the same time, physician shortages (85). These regulatory measures may explain the moderate

annual increase among the medical workforce. To which extent countries’ workforce planning

take account of NPs or other APNs to project student intake, has received little attention in

research and practice. Future research on workforce planning should include NPs in relation

to physician growth and the potential for substitution, such as estimating the number of

“physician-equivalent NPs” as a strategy to ease future projected workforce shortages. In the

Netherlands, for instance, Nurse Specialists have been added to its physician workforce

projection as one scenario to account for substitution (33). Yet, reasons for cross-country

variations in health workforce supply, skill-mix changes across high-income countries and

access to care is one area of research that warrant further high-quality evaluations.

The findings from our literature scoping review show that NPs could cover a range of

approximately 67 to 93% of all primary care services. Findings are largely in line with a

report by the American College of Physicians, suggesting that 60-90% of primary care can be

provided by NPs (86). A previous review showed a lower range of 30% to 70% of physician-

provided activities that could be taken over by NPs, yet comparability is limited, since the

review covered NPs and other non-physician providers (31). Yet, the number of empirical

studies we identified is small, does not take into account variations in specialty areas, is

based on small sample sizes and was conducted in different provider contexts. Hence the

findings require cautious interpretation of the data and call for more research in the field.

This study shows a rapid yearly increase of the NP workforce, which suggests more attention

should be paid to the monitoring of this workforce in the future to expand capacity and access

to healthcare services. To date, data on the NP workforce is not covered in international health

workforce databases, such as the WHO, OECD, or international nursing bodies and

associations. Most data is publicly available or available upon request from the respective

nursing regulatory bodies’ websites or other data holders. In the U.S. with the numerically

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largest workforce, data availability is limited, a barrier for the monitoring of the workforce.

Integrating NPs in health workforce data and intelligence systems at national and international

level is therefore critical for their development, education and monitoring.

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CONCLUSIONS

Nurse Practitioners are a rapidly growing workforce internationally, growing faster than the

medical profession in the six countries studied. Data on the size and growth of NPs are

available in all six countries, however, with variations in quality and completeness,

particularly on time trends. Information on the extent of potential physician substitution effect

is limited, yet, critical for workforce planning. As this workforce grows, improving data

availability and monitoring as part of the overall health workforce is critical to inform

educational capacity, uptake in practice and workforce planning.

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a) Contributorship statement

CBM had the main role in the study design, data collection, and analysis, and wrote the

manuscript. HB contributed to the identification of U.S. data and the literature review, and

was involved in the revisions of the manuscript. LHA and RB gave overall guidance on the

study, the methodology, and reviewed the paper. All authors read, commented upon, and

approved the final manuscript.

Acknowledgements: We are grateful to the Dutch Registration Commission for Nurse

Specialists in the Netherlands (Registratiecommissie Specialismen Verpleegkunde, RSV) for

their support in providing time series data and important additional contextual information.

Moreover, we thank the 93 country experts who participated in the survey. In particular, we

thank the following country experts for providing additional information on data sources:

Julianne Bryce, Australian Nursing and Midwifery Federation; Miranda Laurant, HAN

University of Applied Sciences, Faculty of Health and Social Studies, the Netherlands;

Marieke Kroezen, Catholic University Leuven, Belgium; Jenny Carryer, Massey University

and College of Nurses, New Zealand; Anne-Marie Brady, Trinity College Dublin, Republic of

Ireland; Barbara Todd, Hospital University of Pennsylvania; Kenneth Miller, American

Association of Nurse Practitioners.

b) Competing interests

All authors have completed the ICMJE uniform disclosure form at

www.icmje.org/coi_disclosure.pdf and declare: CB Maier had financial support for the

TaskShift2Nurses Study from the Commonwealth Fund and B. Braun Foundation, through

the Harkness Fellowship, LH Aiken received funding from the National Institutes of Health

(NIH), National Institute of Nursing Research. The funders had no role in the research. The

authors did not have financial relationships with any other organisation that might have an

interest in the submitted work, nor do they possess any other relationships or activities that

may have influenced the submitted work.

c) Funding

This work was supported by The Commonwealth Fund and the B. Braun Foundation, through

the Harkness Fellowship (Maier), and the National Institutes of Health, National Institute of

Nursing Research (Grant No. T32NR007104, Aiken, PI). The views presented here are those

of the authors and should not be attributed to the funders who had no role in the study.

d) Data sharing statement

The data on the total number of Nurse Practitioners are available in the manuscript. All other

data (e.g. OECD data) are publicly available.

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References

1. Cometto G, Boerma T, Campbell J, Dare L, Evans T. The Third Global Forum: framing the

health workforce agenda for universal health coverage. Lancet Glob Health. 2013;1(6):e324-5.

2. World Health Organization. A Universal Truth: No Health Without a Workforce. Third Global

Forum on Human Resources for Health Report. Global Health Workforce Alliance and World Health

Organization, 2013 November 2013. Report No.: Forum Report, Third Global Forum on Human

Resources for Health.

3. OECD. Health Workforce Policies in OECD Countries: Right Jobs, Right Skills, Right Places.

Paris: 2016.

4. International Council of Nurses. International Council of Nurses: Definition and characteristics

for nurse practitioner/advanced practice nursing roles Geneva2002 [updated October 2014; cited

2016 April]. Available from: https://acnp.org.au/sites/default/files/33/definition_of_apn-np.pdf.

5. World Health Organization. Task shifting to tackle health worker shortages.

WHO/HSS/200703. 2007.

6. World Health Organization. Task shifting: rational redistribution of tasks among health

workforce teams: global recommendations and guidelines. Geneva: World Health Organization,

2008.

7. Stanik-Hutt J, Newhouse RP, White KM, Johantgen M, Bass EB, Zangaro G, et al. The Quality

and Effectiveness of Care Provided by Nurse Practitioners. The Journal for Nurse Practitioners.

2013;9(8):492-500.e13.

8. Martinez-Gonzalez NA, Tandjung R, Djalali S, Huber-Geismann F, Markun S, Rosemann T.

Effects of physician-nurse substitution on clinical parameters: a systematic review and meta-analysis.

PLoS One. 2014;9(2):e89181.

9. Martinez-Gonzalez NA, Djalali S, Tandjung R, Huber-Geismann F, Markun S, Wensing M, et al.

Substitution of physicians by nurses in primary care: a systematic review and meta-analysis. BMC

Health Serv Res. 2014;14:214.

10. Martinez-Gonzalez NA, Rosemann T, Tandjung R, Djalali S. The effect of physician-nurse

substitution in primary care in chronic diseases: a systematic review. Swiss Med Wkly.

2015;145:w14031.

11. Mundinger MO. Advanced-practice nursing--good medicine for physicians? N Engl J Med.

1994;330(3):211-4.

12. Martin-Misener R, Bryant-Lukosius D, Harbman P, Donald F, Kaasalainen S, Carter N, et al.

Education of advanced practice nurses in Canada. Nurs Leadersh (Tor Ont). 2010;23 Spec No

2010:61-84.

13. Gagan MJ, Boyd M, Wysocki K, Williams DJ. The first decade of nurse practitioners in New

Zealand: A survey of an evolving practice. J Am Assoc Nurse Pract. 2014;26(11):612-9.

14. Ter Maten-Speksnijder A, Grypdonck M, Pool A, Meurs P, van Staa AL. A literature review of

the Dutch debate on the nurse practitioner role: efficiency vs. professional development. Int Nurs

Rev. 2014;61(1):44-54.

15. MacLellan L, Higgins I, Levett-Jones T. Medical acceptance of the nurse practitioner role in

Australia: A decade on. J Am Assoc Nurse Pract. 2014(10):2014 Jun 4.

16. Begley C, Elliott N, Lalor J, Coyne I, Higgins A, Comiskey CM. Differences between clinical

specialist and advanced practitioner clinical practice, leadership, and research roles, responsibilities,

and perceived outcomes (the SCAPE study). J Adv Nurs. 2013;69(6):1323-37.

17. NHS Education for Scotland. Advanced Nursing Practice Toolkit. Current issues in

regulation2012 September 2015. Available from:

http://www.advancedpractice.scot.nhs.uk/regulatory-guidance/current-issues-in-regulation.aspx

18. Chamberlain P, Brown CH, Saldana L. Observational measure of implementation progress in

community based settings: the Stages of Implementation Completion (SIC). Implement Sci.

2011;6:116.

19. Pulcini J, Jelic M, Gul R, Loke AY. An International Survey on Advanced Practice Nursing

Education, Practice, and Regulation. Journal of Nursing Scholarship. 2010;42(1):31-9.

Page 23 of 39


BMJ Open

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960

on Novem


http://bmjopen.bm

j.com/

BM



ber 2016. Dow

nloaded from



24

20. Delamaire M-L, Lafortune G. Nurses in advanced roles: A description and evaluation of

experiences in 12 developed countries. OECD Health Working Paper 2010;54 (DELSA/HEA/WD/HWP

(2010)5).

21. Heale R, Rieck Buckley C. An international perspective of advanced practice nursing

regulation. Int Nurs Rev. 2015;62(3):421-9.

22. Maier CB. The role of governance in implementing task-shifting from physicians to nurses in

advanced roles in Europe, U.S., Canada, New Zealand and Australia. Health Policy.

2015;119(12):1627-35.

23. Carney M. Regulation of advanced nurse practice: its existence and regulatory dimensions

from an international perspective. J Nurs Manag. 2016;24(1):105-14.

24. Freund T, Everett C, Griffiths P, Hudon C, Naccarella L, Laurant M. Skill mix, roles and

remuneration in the primary care workforce: Who are the healthcare professionals in the primary

care teams across the world? Int J Nurs Stud. 2015;52(3):727-43.

25. Spetz J, Fraher E, Li Y, Bates T. How many nurse practitioners provide primary care? It

depends on how you count them. Med Care Res Rev. 2015;72(3):359-75.

26. Hooker RS, Brock DM, Cook ML. Characteristics of nurse practitioners and physician

assistants in the United States. J Am Assoc Nurse Pract. 2015.

27. Kleinpell R, Goolsby MJ. American Academy of Nurse Practitioners National Nurse

Practitioner Sample Survey: Focus on acute care. Journal of the American Academy of Nurse

Practitioners. 2012;24(12):690-4.

28. Doescher MP, Andrilla CHA, Skillman SM, Morgan P, Kaplan L. The Contribution of Physicians,

Physician Assistants, and Nurse Practitioners Toward Rural Primary Care Findings From a 13-State

Survey. Medical Care. 2014;52(6):549-56.

29. Sangster-Gormley E, Martin-Misener R, Downe-Wamboldt B, Dicenso A. Factors affecting

nurse practitioner role implementation in Canadian practice settings: an integrative review. J Adv

Nurs. 2011;67(6):1178-90.

30. Lowe G, Plummer V, Boyd L. Nurse practitioner roles in Australian healthcare settings.

Nursing Management - UK. 2013;20(2):28-35.

31. Richardson G, Maynard A. Fewer doctors? More nurses? A review of the knowledge base of

doctor-nurse substitution. York: Centre for Health Economics, York Health Economics Consortium,

University of York, 1995 Contract No.: 135.

32. Laurant M, Reeves D, Hermens R, Braspenning J, Grol R, Sibbald B. Substitution of doctors by

nurses in primary care. Cochrane Database of Systematic Reviews. 2005(2).

33. Advisory Committee on Medical Manpower Planning (Capaciteitsorgaan). The 2013

Recommendations for Medical Specialist Training. In the medical, dental, clinical, technological and

mental health areas of training. Utrecht2013 [cited 2015 September]. Available from:

http://www.capaciteitsorgaan.nl/Portals/0/capaciteitsorgaan/publicaties/Capaciteitsplan%202013/D

EFINITIEF%20hoofdrapport%20engels%20compl.pdf

34. OECD Health Statistics. OECD Health Statistics 2015. Definitions, sources and methods.

Metadata. OECD, 2015 November 2015. Report No.

35. The Joanna Briggs Institute. The Joanna Briggs Institute Reviewers’ Manual 2015.

Methodology for JBI Scoping Reviews. The Joanna Briggs Institute (JBI), 2015.

36. Maier CB, Aiken LH. Task-shifting from physicians to nurses in primary care in 39 countries: a

cross-country comparative study. European Journal of Public Health. In press.

37. Kaiser Family Foundation. Total Number of Nurse Practitioners, by Gender. State Health

Facts: Kaiser Family Foundation; 2015 [cited 2015 August]. Available from: http://kff.org/other/state-

indicator/total-number-of-nurse-practitioners-by-gender/.

38. American Association of Nurse Practitioners. AANP - about us - historical timeline: American

Association of Nurse Practitioners (AANP); 2015 [cited 2015 December]. Available from:

https://www.aanp.org/about-aanp/historical-timeline.



Page 24 of 39


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http://bmjopen.bm

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BM



ber 2016. Dow

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25





42. Armstrong R, Hall BJ, Doyle J, Waters E. Cochrane Update. 'Scoping the scope' of a cochrane

review. Journal of public health (Oxford, England). 2011;33(1):147-50.

43. Cacchione PZ. The Evolving Methodology of Scoping Reviews. Clinical nursing research.

2016;25(2):115-9.

44. Population Statistics [Internet]. OECD.Stat. 2015 [cited December 2015]. Available from:

http://stats.oecd.org/Index.aspx?DatasetCode=POP_FIVE_HIST.

45. Healthcare Resources: Physicians [Internet]. OECD.Stat. 2015 [cited December 2015].

Available from: http://stats.oecd.org/index.aspx?DataSetCode=HEALTH_STAT.

46. Dutch health professional register (BIG register). Numbers [Cijfers] of health professionals:

Dutch Ministry of Health, Welfare and Sports; 2015 [cited 2015 December]. Available from:

https://www.bigregister.nl/overbigregister/cijfers/.

47. Rowland D. Demographic Methods and Concepts. New York: Oxford University Press; 2003.

48. Reinhardt UE, Hussey PS, Anderson GF. Cross-national comparisons of health systems using

OECD data, 1999. Health Aff (Millwood). 2002;21(3):169-81.

49. Brownson RC, Boehmer TK, Luke DA. Declining rates of physical activity in the United States:

what are the contributors? Annual review of public health. 2005;26:421-43.

50. Anderson GF, Reinhardt UE, Hussey PS, Petrosyan V. It's the prices, stupid: why the United

States is so different from other countries. Health Aff (Millwood). 2003;22(3):89-105.

51. Canadian Institute for Health Information. Regulated Nurses, 2014. Health Workforce

Database: Canadian Institute for Health Information; 2015 [cited 2015 November]. Available from:


52. Nursing and Midwifery Board of Ireland. Statistics. Register statistics 2014 2015 [cited 2015

November]. Available from: http://www.nursingboard.ie/en/statistics.aspx.

53. Nursing and Midwifery Board of Australia. Statistics. 2015 June 2015. Report No.


55. Dutch Nurse Specialist Registry. Unpublished data on Nurse Specialists (Verpleegkundig

Specialisten), 2009 to 2015, received upon request. 2015.

56. U.S. HRSA National Center for Health Workforce Analysis. Highlights From the 2012 National

Sample Survey of Nurse Practitioners. Rockville, Maryland: U.S. Department of Health and Human

Services, 2014, 2014.

57. OECD;. OECD Health Statistics 2015. Definitions, Sources and Methods. Physicians licensed to

practice OECD, OECD Health Statistics 2015, 2015 July 2015. Report No.

58. OECD;. OECD Health Statistics 2015. Definitions, Sources and Methods. Professionally active

physicians. OECD, OECD Health Statistics 2015, 2015.















Page 25 of 39


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http://bmjopen.bm

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BM



ber 2016. Dow

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26





69. Spitzer WO, Sackett DL, Sibley JC, Roberts RS, Gent M, Kergin DJ, et al. The Burlington

randomized trial of the nurse practitioner. N Engl J Med. 1974;290(5):251-6.

70. van der Biezen M, Schoonhoven L, Wijers N, van der Burgt R, Wensing M, Laurant M.

Substitution of general practitioners by nurse practitioners in out-of-hours primary care: a quasi-

experimental study. J Adv Nurs. 2016.

71. Wijers N, van der Burgt R, Laurant M. Verpleegkundig Specialist biedt kansen.

Onderzoeksrapport naar de inzet van de verpleegkundig specialist op de spoedpost in Eindhoven.

[Specialist Nursing offers opportunities. Research report into the use of the specialist nurse at the

emergency station in Eindhoven]. Nijmegen: IQ healthcare, UMC St Radboud; Eindhoven: KOH

Foundation: 2013.

72. Laurant M. Out of hours primary care. International Innovation 2013 [cited 2015 December].

Available from:

http://rcpsc.medical.org/publicpolicy/imwc/out_of_hours_primary_care_interview_miranda_laurant

.pdf.

73. DiCenso A, Bryant-Lukosius D, Martin-Misener R, Donald F, Abelson J, Bourgeault I, et al.

Factors enabling advanced practice nursing role integration in Canada. Nurs Leadersh (Tor Ont).

2010;23 Spec No 2010:211-38.

74. Minto R. Barriers on nurse practitioner journey. Nurs N Z. 2008;14(6):4.

75. Begley C, Murphy K, Higgins A, Cooney A. Policy-makers' views on impact of specialist and

advanced practitioner roles in Ireland: the SCAPE study. Journal of Nursing Management.

2014;22(4):410-22.

76. Scanlon A, Cashin A, Bryce J, Kelly JG, Buckely T. The complexities of defining nurse

practitioner scope of practice in the Australian context. Collegian. 2016;23(1):129-42.

77. Cashin A. Collaborative arrangements for Australian nurse practitioners: A policy analysis.

Journal of the American Association of Nurse Practitioners. 2014;26(10):550-4.

78. Parliament of New Zealand. Misuse of Drugs Amendment Regulations 2014. 2014/199. 2014.

79. van Meersbergen D. Task-shifting in the Netherlands. World Medical Journal (WMA).

2011;57(4):126-30.

80. Phillips SJ. 28th Annual APRN Legislative Update: Advancements continue for APRN practice.

Nurse Pract. 2016;41(1):21-48.

81. Kroezen M, van Dijk L, Groenewegen PP, Francke AL. Nurse prescribing of medicines in

Western European and Anglo-Saxon countries: a systematic review of the literature. BMC Health Serv

Res. 2011(10):2011 May 27;11:127.

82. Government of Canada. Controlled Drugs and Substances Act. New Classes of Practitioners

Regulations. Canada Gazette. 2012;146(24).

83. Australian Government. Health Legislation Amendment (Midwives and Nurse Practitioners)

Act 2010. No. 29, 2010. C2010A00029. 2010.

84. Phillips SJ. 27th Annual APRN legislative update: advancements continue for APRN practice.

Nurse Pract. 2015;40(1):16-42.

85. Ono T, Lafortune G, Schoenstein M. Health Workforce Planning in OECD Countries: A Review

of 26 Projection Models from 18 Countries. OECD Health Working Papers [Internet]. 2013 October

2015 [cited 2015 October]; No. 62.

86. American College of Physicians. Nurse Practitioners in Primary Care. Philadelphia: American

College of Physicians, 2009.

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Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following data sources: (37, 46, 51-55),

Notes: *2015: except for Canada, Ireland: 2014; Data on RNs include NPs, U.S.=United States, NP= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active, R=Registered/Licensed to practice, RNs=Registered Nurses, Caveats: Netherlands (nurse specialists): an estimated 12 test accounts are in the

database (0.4%) that cannot be filtered out (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January 2016).

Figure 1: Total number of NPs 279x215mm (300 x 300 DPI)

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Sources: Authors’ calculations, based on the following data sources: (37, 51-56), Data on physicians based on the OECD 2015 database (45), drawn from the following primary data sources: United States: American Medical Association (AMA); Canada: Canadian Institute for Health Information (CIHI); Netherlands: The BIG register, Australia: Australian Institute of Health and Welfare (AIHW), New Zealand: Medical Council Medical

Register (57, 58).

Notes: *Year 2013; except for Ireland (2014), United States (2012) depending on years covered by OECD physician data; NPs= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active,

R=Registered/Licensed to practice, U.S.=United States, Caveats: Netherlands (Nurse specialists): an estimated 12 test accounts are in the database that cannot be filtered out (personal communication, with

registry advisor at Verpleegkundig Specialisten Register, 29 January 2016). Figure 2: Nurse Practitioner d 279x215mm (300 x 300 DPI)

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Supplement

A descriptive, cross-country analysis of the nurse practitioner

workforce in six countries: size, growth, physician substitution potential

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Table of Content

1. Information on the literature scoping review ........................................................................................ 3

1.1 Background on literature scoping reviews ........................................................................................ 3

1.2 Research questions, search strategy and data analysis ...................................................................... 3

2. Extent of NPs substituting fully or partially for physicians: overview of empirical studies................. 7

3. Quality of the evidence ....................................................................................................................... 10

4. References ........................................................................................................................................... 11

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1. Information on the literature scoping review

1.1 Background on literature scoping reviews

Literature scoping reviews have evolved over the last 20 years as an additional method to

systematic literature reviews for searching the literature and synthesising the evidence on a

specific topic, concept or research question (1-3). While systematic literature reviews usually

focus on narrowly defined research questions, usually following PICO elements (Participants,

Interventions, Comparisons, Outcomes) (4), literature scoping reviews start at an earlier stage

and with a broader scope, allowing for a broader approach to research questions or objectives (2,

3). Research questions are therefore typically defined per PCC (Population, Concept, Context)

instead of PICO elements (3). According to Cacchione (1), there are three distinctive features of

scoping reviews, first to map the research and key concepts underpinning a research question or

concept, second, to provide a synthesis and analysis of a wide range of research and grey or non-

research material and third, include various, heterogeneous sources instead of focusing on the

best evidence only.

We chose this study design to explore what evidence is available on the concept of physician

substitution effect, measuring the extent to which NPs can substitute partially or fully for

physicians. This research objective is relevant to workforce planners aiming at analysing the

potential of NPs for in expanding access to primary care, specific specialty areas or regions (e.g.

rural and remote areas). We aimed to identify all existing evidence in the field, instead of

restricting the review to Randomised Controlled Trials (RCTs) or other high-quality studies only.

We followed the methods established by the Joanna Briggs Institute’s manual on conducting

scoping reviews (3).

1.2 Research questions, search strategy and data analysis

Review question(s)

The following research question guided the review based on the PCC elements (Population,

concept, context):

What evidence exists on the concept of substitution, defined by Nurse Practitioners substituting

fully or partially for physicians with a focus on primary care, focusing on studies conducted in

six countries (Australia, Canada, Ireland, Netherlands, New Zealand, and the United States)?

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Literature search

The literature search covered Medline, CINAHL, Google Scholar, and grey literature, to identify

what studies, concepts and literature exists that have quantified the extent to which NPs are able

to substitute for physicians. We deliberately aimed to cover literature from peer-reviewed

journals and grey literature to explore what information is available. In addition, we performed

snowballing and asked country experts for additional information.

Inclusion criteria of the search:

- All studies (irrespective of the empirical method/methodology used) that quantify the

extent of advanced practice of NPs to estimate their potential in substituting for

physicians. The operational definition included the following: “studies calculating either

the percentage of typical medical activities that can be safely performed by NPs; or

methods on the extent of services that can be provided by NPs” (5, 6).

- The review was restricted to NPs only (Nurse Specialists in the Netherlands) working in

primary care, such as family health, community health, including pediatric (routine)

services, all primary care provider models (solo, group practices, health centres),

including out-of-hours care, emergency ambulatory care

- Studies conducted in one of the following countries: Australia, Canada, Ireland,

Netherlands, New Zealand, and the United States

- Search was conducted in English language

- No restrictions on years

Exclusion criteria:

- Studies that did not calculate in quantitative measures/terms the extent to which NPs can

provide the same services as physicians, hence partially or fully substitute for physicians

- Studies conducted outside the six countries

- All care services provided that are inpatient care or specialty services, such as secondary

and tertiary care, including hospital care, rehabilitation (if inpatient), psychiatric care if

inpatient or outpatient, nursing homes

- Non-NP roles, such as Physician Assistants, Clinical Nurse Specialists, nurse anesthetists,

nurse midwives, practice nurses, registered nurses.

Types of studies

All relevant studies were included that evaluate or analyse the potential physician

substitution effect of NPs, including RCTs (randomised controlled trials), before-after

studies, or any other studies with physicians as comparator groups, including studies

published in peer-reviewed journals and grey literature.

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Search terms used

Search terms included various combinations of the MeSH terms and individual search terms

on the concept of physician substitution by nurse practitioners with a focus on primary care.

The following search terms were used:

Set #1 [NPs or similar advanced practice nursing roles]

"Nurse Practitioners"[Mesh] OR nurse practitioner* [TW] OR “advanced practice nurse”

[TW] OR “advanced practice registered nurse” [TW] OR “advanced nursing practice” [TW]

OR “nurse specialist” [TW] OR “nurse led” [TIAB] OR “nurse-led” [TIAB]

Set #2 [concept of substitution]

Substitut* [tw] OR visit [all] OR contribution [tw] OR task-shifting [tiab] OR task shifting

[tiab] OR task sharing [tiab] OR delegation [tiab] OR re-allocation [tiab] OR forecasting

[tiab] OR planning [tiab]

Set #3 [primary care]

"primary care" [Mesh] OR primary care [tw] OR community [tiab] OR primary health care

[tw] OR community health [tw]

Combined Set 1 AND Set 2 AND Set 3

The search was conducted covering all years up to May 30, 2016.

Search results

The search yielded a total of 1,022 results (through databases, google scholar, snowballing and

additional information by experts). After removal of duplicates (n=31), the titles of 991 records

were screened according to the exclusion criteria. Of those, 768 were excluded, of which the

major reasons were as follows: other, none NP roles (e.g. practice nurses, community nurses,

nurse anaesthesists; or other non-physician roles, e.g. physician assistants, or a mix of different

providers), no physician comparator group, no calculation or quantification of the “physician

substitution potential” (e.g. percent of all visits performed by NPs, % of physician tasks

performed by NPs, etc). In a next step, the abstracts of 223 records were examined of which the

full-text of 46 studies were screened. Out of those, five papers met the inclusion criteria and were

relevant, as they had provided some form of quantification of the extent of substitution effect

(three peer-reviewed journal articles, and two sources of grey literature) reporting findings from

three different empirical studies. The search was conducted in English, however, snowballing

and contacts with individual researchers resulted in few non-English publications, of which one

Dutch report was included.

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In addition, two reviews, published as a working paper and a book were identified (6, 7) that

aimed at providing an overview of studies quantifying the % of physician substitution potential.

They were excluded from the main results because they included several groups of non-

physician providers and did not exclusively focus on NPs. However, we provide an overview of

the findings below to set our findings in context.

Data analysis and synthesis involved the extraction of information on the country, research aims,

study design and year(s) of the study, service delivery settings, number and characteristics of

participants, and the results. A narrative synthesis was performed, pooled analysis was not

possible, due to the large heterogeneity of the studies and material identified.

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2. Extent of NPs substituting fully or partially for physicians: overview of empirical studies

Table S 1. Detailed overview of empirical studies on the percent of physician substitution effect by NPs

Country Aims/Purpose Study design

(Years) Setting Participants Results Reference

Canada To assess the

effects of

substituting

NPs for

physicians in

primary care

RCT (1971-

1972)

Two large

suburban

Ontario

family

practices

consisting

of 1

physician

and 1 NP

each.

Families

were

randomised

to care by a

physician or

NP. 529

families

(1,398

individuals)

randomised

to each

physician;

270 families

(765

individuals)

to each NP.

Total patient

N = 1,598

families

(4,325

individuals)

67% of all primary care patient visits could be

provided by NPs.

Care delivery was similar between physicians

and NPs. There were no statistically significant

differences between patients seen by NPs

compared to patients seen by physicians were

found in patient functional capacity, indexes of

social and emotional function, mortality, or

satisfaction with care.

Practices were able to increase practice size and

patient volume with the addition of an NP in the

practice.

(8)

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Netherlands To compare the

number of

patients and

caseloads

between NPs

and GPs in out-

of-hours

services

Quasi-

experimental

study (April

2011 to July

2012)

Out-of-

hours

primary

care

Intervention:

one NP and

four GPs,

control: five

GPs working

in out-of-

hours

services.

Total patient

N=12,092

from one GP

cooperative

extracted

from medical

records

75-83% of clinical activities in out-of-hours

primary care settings (weekend shifts in GP

practices) could be taken over by Nurse

Specialists (Verpleegkundig Specialist)

More than 77% of patients fit the scope-of-

practice of Nurse Practitioners (Verpleegkundig

Specialist) in out-of-hours care.

On average 16.3% of all patients were treated by

NPs, whereas 20.9% of patients were treated by

GPs. GPs were more likely than NPs to treat

older patients, patients with digestive,

cardiovascular and neurological complaints and

more urgent cases, whereas NPs treated more

patients with skin and respiratory diseases.

(9, 10)

(11)

U.S. To assess

practice

activities of

rural primary

care physicians

and NPs.

Self-report,

mailed survey

to a random

sample of

4,000

physicians and

3,000 NPs with

rural addresses

(all specialties)

(2011-2012)

Rural

primary

care in 13

states with

at least 2

from each

U.S. Census

Regions (4

regions).

Final sample

included 788

primary care

physicians

(response

rate: 25%);

and 918

primary care

NPs (40%)

75-93% of weekly primary care outpatient visits

can be provided by NPs.a

In the outpatient setting, primary care clinical

activitiesb were comparable between physicians

and NPs in the outpatient setting.

Average weekly outpatient visit quantity was

25% lower for NPs (p<0.001) than physicians,

this difference decreased to 10% for NPs

(P<0.001) compared to physicians in the

multivariate analyses.

(12)

Source: see directly in the table

Notes: NP = nurse practitioners; RCT = randomised controlled trial; GP = general practitioner a In an unadjusted regression model, NP average weekly number of outpatient visits was 75% of physician volume. In an adjusted model (age, sex,

geographic location, and practice setting), NP average weekly number of outpatient visits was 93% of physician volume. b On average, physicians conducted more well-child visits than NPs (12.6 vs. 7.4, p <0.001). Differences for prenatal visits and minor procedures

were non-significant.

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Table S 2. Overview of reviews on the percent of physician substitution effect by NPs (and other non-physician providers)

Country Aims/Purpose Study design

(Years) Setting Participants Results Reference

Reviews

U.S.-

focused

studies

To assess the

delegation of

primary care

office visits to

NPs and other

“health

practitioners”

Overview of

studies (Dates

of NP-focused

studies: 1968-

1974)

Primary

Care – adult

and

pediatric

17 studies

included with

7 focusing on

delegation of

visits to NPs.

75% of adult primary care and

90% of pediatric primary care

can be safely delegated to NPs

(7)

International

scope

(studies

from U.S.,

Canada,

UK)

To assess the

what

percentage of

physicians’

tasks can be

performed by

nurses by

synthesizing

the evidence on

doctor-nurse

substitution

Review of

studies

All care

settings

12 studies

including

several non-

physician

providers

(including

NPs, practice

nurses,

physician

assistants) in

intervention

group

30 to 70% of the tasks

performed by physicians could

be performed by nurses or other

non-physician providers

(including NPs, registered

nurses, practice nurses, other

practitioners)

(6)

Source: see directly in the table

Notes: NP = nurse practitioner, U.S.=United States

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3. Quality of the evidence

The quality of the records of studies included was highly variable, but mostly of limited quality.

Of the five relevant papers, three were studies published in peer-reviewed journals, and two other

sources were retrieved via google scholar and snowballing. The comparatively highest quality

study was one study in Canada which findings stem from a small RCT involving two Ontario

family practices (8). The study shows the smallest risk of bias compared to the other literature,

yet dates back more than 40 years and was based on a small provider base (8). One more recent

study, conducted in 2011-12 in the Netherlands was based on a quasi-experimental design, with

moderate to high risk of bias, from which three papers reported findings (9-11) with the main

paper being (11). Of the remaining source included from the U.S., one recent study was based on

a survey to over 7,000 physicians and NPs in rural areas, covering all specialty areas to assess

the extent of practice, frequency of visits and primary care physician substitution potential (12).

Yet, its generalisability is limited since focused on rural practice. In conclusion, the evidence

available to assess the extent to which NPs can substitute for physicians faces considerable

limitations, is based on few studies, one of which dates back more than 40 years, calling for

future research in the area.

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4. References

1. Cacchione PZ. The Evolving Methodology of Scoping Reviews. Clinical nursing research. 2016;25(2):115-9. 2. Armstrong R, Hall BJ, Doyle J, Waters E. Cochrane Update. 'Scoping the scope' of a cochrane review. Journal of public health (Oxford, England). 2011;33(1):147-50. 3. The Joanna Briggs Institute. The Joanna Briggs Institute Reviewers’ Manual 2015. Methodology for JBI Scoping Reviews. The Joanna Briggs Institute (JBI), 2015. 4. Higgins JPT, Green Se. Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0. The Cochrane Collaboration, 2011 updated March 2011. Report No. 5. Advisory Committee on Medical Manpower Planning (Capaciteitsorgaan). The 2013 Recommendations for Medical Specialist Training. In the medical, dental, clinical, technological and mental health areas of training. Utrecht2013 [cited 2015 September]. Available from: http://www.capaciteitsorgaan.nl/Portals/0/capaciteitsorgaan/publicaties/Capaciteitsplan%202013/DEFINITIEF%20hoofdrapport%20engels%20compl.pdf 6. Richardson G, Maynard A. Fewer doctors? More nurses? A review of the knowledge base of doctor-nurse substitution. York: Centre for Health Economics, York Health Economics Consortium, University of York, 1995 Contract No.: 135. 7. Record J. Staffing in Primary Care in 1990: Physician replacement and cost savings. New York: Springer Publishing Company; 1981. 8. Spitzer WO, Sackett DL, Sibley JC, Roberts RS, Gent M, Kergin DJ, et al. The Burlington randomized trial of the nurse practitioner. N Engl J Med. 1974;290(5):251-6. 9. Wijers N, van der Burgt R, Laurant M. Verpleegkundig Specialist biedt kansen. Onderzoeksrapport naar de inzet van de verpleegkundig specialist op de spoedpost in Eindhoven. [Specialist Nursing offers opportunities. Research report into the use of the specialist nurse at the emergency station in Eindhoven]. Nijmegen: IQ healthcare, UMC St Radboud; Eindhoven: KOH Foundation: 2013. 10. Laurant M. Out of hours primary care. International Innovation 2013 [cited 2015 December]. Available from: http://rcpsc.medical.org/publicpolicy/imwc/out_of_hours_primary_care_interview_miranda_laurant.pdf. 11. van der Biezen M, Schoonhoven L, Wijers N, van der Burgt R, Wensing M, Laurant M. Substitution of general practitioners by nurse practitioners in out-of-hours primary care: a quasi-experimental study. J Adv Nurs. 2016. 12. Doescher MP, Andrilla CHA, Skillman SM, Morgan P, Kaplan L. The Contribution of Physicians, Physician Assistants, and Nurse Practitioners Toward Rural Primary Care Findings From a 13-State Survey. Medical Care. 2014;52(6):549-56.

Page 39 of 39


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http://rcpsc.medical.org/publicpolicy/imwc/out_of_hours_primary_care_interview_miranda_laurant.pdf

http://rcpsc.medical.org/publicpolicy/imwc/out_of_hours_primary_care_interview_miranda_laurant.pdf


Correction: Descriptive, cross-country analysis of the nursepractitioner workforce in six countries: size, growth,physician substitution potential

Maier CB, Barnes H, Aiken LH, et al. Descriptive, cross-country analysis of the nursepractitioner workforce in six countries: size, growth, physician substitution potential.BMJ Open 2016;6:e011901. Complete publication details of references 36, 39–41, 53,77, 81 and 82 are given below.36. Maier CB, Aiken LH. Task-shifting from physicians to nurses in primary care in

39 countries: a cross-country comparative study. Eur J Public Health 2016. [ePub aheadof print 2 Aug 2016]. doi:10.1093/eurpub/ckw09839. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May

2014. 29-1171 Nurse Practitioners. Bureau of Labor Statistics (BLS), 2014. http://www.bls.gov/oes/current/oes291171.htm (accessed Dec 2015).40. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May

2012. 29-1171 Nurse Practitioners. Bureau of Labor Statistics (BLS), 2012. http://www.bls.gov/oes/current/oes291171.htm (accessed Dec 2015).41. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May

2013. 29-1171 Nurse Practitioners. Bureau of Labor Statistics (BLS), 2013. http://www.bls.gov/oes/current/oes291171.htm (accessed Dec 2015).53. Nursing and Midwifery Board of Australia. Statistics. 2015 June 2015. Report

No. http://www.nursingmidwiferyboard.gov.au/About/Statistics.aspx (accessed Dec 2015).77. Parliament of New Zealand. Misuse of Drugs Amendment Regulations 2014. 2014/

199. 2014. http://www.legislation.govt.nz/regulation/public/2014/0199/latest/DLM6156029.html?search=qs_regulation%40deemedreg_Misuse+of+drugs+act_resel_25_h&p=1 (accessed Dec2015).81. Government of Canada. Controlled Drugs and Substances Act. New Classes of

Practitioners Regulations. Canada Gazette. 2012;146. http://www.gazette.gc.ca/rp-pr/p1/2012/2012-05-05/html/reg1-eng.html (accessed Dec 2015).82. Australian Government. Health Legislation Amendment (Midwives and Nurse

Practitioners) Act 2010. No. 29, 2010. C2010A00029. 2010. https://www.legislation.gov.au/Details/C2010A00029 (accessed Dec 2015).

Open Access This is an Open Access article distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited andthe use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/

BMJ Open 2016;6:e011901corr1. doi:10.1136/bmjopen-2016-011901corr1

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