Reliability and validity of the habitual activity estimation scale (HAES) in patients with cystic fibrosis

Author Proof

APediatric Pulmonology 00:1–9 (2007)

Reliability and Validity of the Habitual Activity EstimationScale (HAES) in Patients With Cystic Fibrosis

Greg D. Wells, PhD,1* Donna L. Wilkes,1 Jane Schneiderman-Walker,1 Maryam Elmi,1

Elizabeth Tullis,2 Larry C. Lands,3 Felix Ratjen,1 and Allan L. Coates1

Summary. Purpose To understand potential benefits of exercise in the cystic fibrosis (CF)

population, there needs to be accurate methods to quantify it. The Habitual Activity Estimation

Scale (HAES) questionnaire has been shown to be a feasible tool to measure physical activity

however the reliability and validity has yet to be determined in the CF population. Methods:

Fourteen (seven male, seven female) patients aged 16.2� 4.2 years with CF participated in this

study. Participants were clinically stable at the time of the study and participating in their habitual

physical activity. To assess reliability, patients completed the HAES and a validated 3-day activity

diary, and wore an ActiGraphTM Accelerometer for two consecutive weeks. Validity was assessed

by comparing the activity results of each of the three instruments over a single week time period.

Results: ICC estimates of reliability for the HAES, diary, and accelerometer were 0.72 (P< 0.0001),

0.76 (P< 0.0001), 0.63 (P<0.0001), respectively. Validity analysis indicated that there were

significant relationships between the participants’ activity results as estimated by the HAES, diary

and accelerometer. Further, significant relationships were detected between activity measures

when broken into morning, afternoon, or evening periods, and between measures from weekday

or weekend days. There were also significant relationships among the three instruments when

recording different activity levels (somewhat inactive, somewhat active, and very active).

Conclusion: The findings of this study suggest that the HAES questionnaire is a reliable and

valid instrument that can be used to assess activities of varying intensity in patients with CF.

Pediatr Pulmonol. 2007; 00:1–9. � 2007 Wiley-Liss, Inc.

Key words: children; adults; cystic fibrosis; activity; measurement.

INTRODUCTION

Physical activity and exercise have been shown to befactors that contribute to the health of patients with cysticfibrosis (CF).1–3 However, it has been documented thatexercise capacity in this group is limited by lung functionand peripheral skeletal muscle function4 nutritionalstatus5–7 as well as the cardio-respiratory system’s abilityto meet the metabolic demands associated with exercise.6

Recent research has shown a trend towards a slower rateof decline in pulmonary function (as assessed by rate ofdecline of FEV1) in female CF patients with higher activitylevels,3 which supports previous results reporting a benefitfor patients with CF participating in regular aerobicexercise8 and more recent results that demonstrate anassociation between physical activity and higher aerobiccapacity in CF patients.9 However, implementing andmaintaining exercise training programs is cost and laborintensive. In addition, once the exercise-training programends, participants often do not continue with the trainingprogram, and the health benefits are lost. Thus, strategiesaimed at monitoring and increasing habitual physicalactivity may be more effective in maintaining andimproving the health and quality of life of people with

CF,10 and therefore a reliable and valid tool to measurephysical activity in the CF population is needed.

Habitual physical activity can be measured by manydifferent methods including (a) doubly labeled water thatmeasures total energy expenditure11 (b) motion sensorssuch as pedometers or accelerometers that measureactivity counts,212 (c) recall questionnaires13 or activity

PPUL-07-0191.R3(20737)

1DepartmentQ1 of Respiratory Medicine, The Hospital for Sick Children,

Toronto, Ontario, Canada.

2Respirology Department, St. Michael’s Hospital, Toronto, Ontario, Canada.

3Division of Respiratory Medicine, Montreal Children’s Hospital, Montreal,

Quebec, Canada.

*Correspondence to: Greg D. Wells, PhD, Division of Respiratory

Medicine, Room 4534, The Hospital for Sick Children, 555 University

Avenue, Toronto, Ontario, Canada M5G 1X8.

E-mail: [email protected]

Received 4 June 2007; Revised 1 October 2007; Accepted 3 October 2007.

DOI 10.1002/ppul.20737

Published online in Wiley InterScience

(www.interscience.wiley.com).

� 2007 Wiley-Liss, Inc.

Author Proof

Adiaries.14 A comprehensive review has been publishedwhich describes each of these techniques in detail.15 Eachmethod assesses different aspects of habitual physicalactivity, and each has definite benefits and drawbacks. Thedoubly labeled water technique is regarded as an accuratemeasure of daily energy expenditure but it is prohibitivelyexpensive.15 While data from activity and motion sensorsmust be cleaned of artifact such as movement whiledriving in a car or bicycling,16 they have been demon-strated to be useful tools to measure the total amount ofphysical activity in children17 and for validation of activityquestionnaires.15 Habitual physical activity as measuredby an activity diary has been shown to correlate with theresults of the doubly labeled water technique.11

The Habitual Activity Estimation Scale (HAES)questionnaire developed by Hay and Cairney13 has severalbenefits over other measurement tools in that (a) it isdesigned to be used in clinical settings, (b) it can becompleted in 15 min during outpatient clinic visitsresulting in completion rates of 100%, (c) the data areeasily and quickly analyzed and can be used to provideimmediate feedback to patients and care givers, and(d) patients >11 years can complete it without assistance,once given proper instruction. The HAES is an importanttool that has been used by CF researchers to show thathigher activity levels are related to improved outcome inpatients with CF.3 Further, the HAES questionnaire hasbeen shown to be a feasible to assess physical activity inpatients with CF310 however validity and reliability haveyet to be fully established in the CF population. Thus, thepurpose of the current research was to test the hypothesisthat the HAES instrument is a reliable and valid instru-ment for the assessment of physical activity in pediatricand adult CF populations.

METHODS

Research Design

This study compared the habitual physical activityscores using the HAES questionnaire with scores from anaccelerometer activity monitor and an activity diary inadolescent and adult patients with CF. Participants werestudied over two consecutive weeks. Results from theactivity measurement tools (accelerometer, activity diary,and HAES) were compared to evaluate the validity andreliability of the HAES. Results from the first week werecompared to the results from week 2 to determinereliability, and results from each instrument werecompared to each other to estimate validity. The researchdesign is presented graphically in Figure 1.

Instrument Comparison Parameters

The activity levels for each instrument were equatedbased on the following four activity categories as

established in the HAES instrument: inactive (IA, lyingdown), somewhat inactive (SI, sitting down), somewhatactive (SA, walking), and very active (VA)Q2, activitiesthat make the subject ‘‘breathe hard and sweat.’’ Theactivity results from the diary were evaluated and groupedas follows: sleeping and lying down were grouped as‘‘inactive,’’ sitting and standing activities were grouped as‘‘somewhat inactive,’’ walking and other low intensityleisure activities were grouped as ‘‘somewhat active’’ andleisure activities of moderate and high intensity and sportsactivities were grouped as ‘‘active.’’ For the accelerom-eter, the activity levels were set as follows: inactive<2,000 counts, somewhat inactive from 2,001 to 5,500counts, somewhat active from 5,501 to 9,500 counts, andvery active >9,501 counts based on the regressionequations developed by Crouter et al.18

Sample and Sampling Procedures

Participants were recruited from the pediatric CFclinic at the Hospital for Sick Children (SK) and theadult CF clinic at St. Michael’s Hospital (SMH) inToronto, Canada. At the time of recruitment, partic-ipants were healthy with no recent history of pulmonaryexacerbation in the preceding 3 months (defined asincreased cough, purulent sputum, and malaise) with anFEV1 of greater than 60% predicted. Subjects were notrecruited if they are unable to participate in theirhabitual physical activity (i.e., due to illness). Writteninformed consent was obtained from the patients whoagreed to participate. Patients had prior experience incompleting the HAES questionnaire and activity diary.At the end of the first week of study, all subjects weretelephoned to remind them to complete the first weeks’forms and have any questions answered. This wasrepeated at the end of the second week. Once the2 weeks of study were completed, subjects returnedquestionnaires, diaries and accelerometers by mail in apre-paid stamped envelope.

Fig. 1. Research design.

2 Wells et al.

Author Proof

AHAES Questionnaire

Patients completed the HAES questionnaire13 for atypical weekday (Tuesday, Wednesday, or Thursday) andSaturday in each of the 2 weeks that were studied.Percentage of time awake was documented in each of fouractivity categories: inactive, somewhat inactive, some-what active, and very active. The use of wakeup, bed, andmeal times allowed the calculation of the total number ofhours per day spent in each of the four activity categories.Total activity (TA) was calculated as SAþVA foreach day. The use of this questionnaire with CF patientshas been described previously.3

3-Day Activity Diary

A 3-day version of Bratteby’s 7-day diary11 was alsoused to record activity levels. Participants recorded twotypical weekdays (Tuesday, Wednesday, or Thursday) andone typical Saturday within each of 2 weeks studied ratherthan the entire week as had been done in the Bratteby7-day diary. A similar 3-day diary has been describedpreviously.14 The 3-day activity diary (vs. 7 days) wasused to (a) match, as closely as possible, the data collectedusing the diary to the data collected with the HAES and(b) make the recording process less demanding on theparticipants to improve compliance. The Bratteby diaryhas been validated against doubly labeled water, and thuswould serve as a useful tool against which to compare theresults of the HAES. The type and intensity of activitywere recorded in 15-min blocks for each of the three days,and this was matched to the four activity level categoriesthat are employed by the HAES instrument.

Accelerometer

An electronic activity monitor, an ActiGraphTM Tri-Axial Accelerometer (model 7164), was used to obtain anobjective measure of overall activity level. Participantswore the accelerometer for 14 consecutive days on theright hip, just below the waist line and were instructed towear it at all times, except while sleeping or when thedevice could get completely wet (e.g., showering,swimming). The recording epoch was set to 15 min tomatch the recording times of the activity diary. Oncereturned, activity counts were downloaded and processedvia software supplied with the accelerometers.

Data Analysis

Data from the accelerometer, activity diary and HAESquestionnaire were compared for the same daily period(morning, afternoon, or evening), day (weekdayor weekend), and intensity level (inactive, somewhatinactive, somewhat active, very active). Data fromthe weekday (Tuesday and Thursday) activity levels were

averaged to give a single weekday value for the diary andaccelerometer so as to match with the weekday HAESquestionnaire which asks the subject to recall activity for atypical Tuesday, Wednesday, or Thursday. The activityscores from each instrument were summarized usingdescriptive statistics. For reliability, intra-class correlationcoefficients (Model 2,2) were calculated for the results ofeach of the instruments from weeks 1 to 2. Validity wasestimated by intra-class correlation coefficient (Model2,1) single measure analysis of the activity resultsobtained from each instrument to estimate the strengthof the relationship between each of the instruments(HAES vs. diary, HAES vs. accelerometer, diary vs.accelerometer). For the validity analysis only, wehypothesized that the accelerometer may not be able toaccurately distinguish between activity levels where thesubject was lying down or sitting (inactive and somewhatinactive), and therefore we decided to group these twoactivity levels for the validity analysis to ensure that thecomparisons between instruments were as consistent aspossible. The data were analyzed using SPSS 11.0 (SPSSfor Windows, SPSS, Inc., Chicago, IL) and SAS 9.1 (SASfor Windows, Cary, NC) Statistical significance wasconsidered to be P< 0.05.

RESULTS

Participant Characteristics

Fourteen (seven male, seven female) patients aged16.2� 4.2 years with CF from the CF clinics at theHospital for Sick Children and St. Michael’s Hospitalparticipated in this study. Participants were clinicallystable at the time of the study (FEV1 >70% predicted) andparticipating in their ‘‘habitual’’ physical activity. Allsubjects were assessed on basic spirometry and performedan incremental exercise test to exhaustion as part of theirregular clinic visit. The descriptive characteristics of thesubjects are presented in Table 1.

Habitual Activity Estimation Scale Results

Completion rate for the HAES in week 1 was 100% andfor week 2 was 87%. Results are presented in Table 2.There were no significant differences between female andmale activity levels measured by the HAES foreither weekday (P¼ 0.42) or weekend (P¼ 0.87).

3-Day Activity Diary Results

Completion rate for the Activity Diary in week 1 was100% and for week 2 was 87%. Results are presented inTable 3. There were no significant differences betweenfemale and male activity levels measured by the activitydiary for either weekday (P¼ 0.69) or weekend(P¼ 0.74).

HAES Reliability and Validity 3

Author Proof

AAccelerometer Results

The participants wore the accelerometer for 14consecutive days. All (100%) of the accelerometer datafrom week 1 and 87% of the data from week 2 wereacceptable, more specifically two of the participants didnot wear the accelerometer on several days during week 2.Mean results are presented in Table 4. There were nosignificant differences between female and male activitycounts measured by the accelerometer for either weekday(P¼ 0.19) or for weekend (P¼ 0.72).

Instrument Comparison Overview

Intra-class correlation coefficient estimates of reliabil-ity for the HAES, diary and accelerometer were 0.72(P< 0.0001), 0.76 (P< 0.0001), 0.63 (P< 0.0001),respectively (see Table 5). There were no overall differ-ences among the participants’ activity levels or in the veryactive category as estimated by the HAES and diary orHAES and accelerometer (see Table 6). Further, therewere no significant differences between activity measuresamong the three instruments when broken into morning,afternoon, or evening periods, or between measuresfrom weekday or weekend days. There were no significant

differences among the three instruments when recording‘‘very active’’ intensity levels. However, the three instru-ments detected significantly different activity measuresduring the inactive/somewhat inactive (P¼ 0.02) andsomewhat active (P¼ 0.001) intensity levels. In general,the participants reported more time spent in the ‘‘some-what inactive’’ and ‘‘somewhat active’’ categories whenusing the HAES and diary than was detected using theaccelerometer (see Tables 2–4).

Results of the Reliability Analysis

Intra-class correlation coefficient analysis suggestedsignificant reliability from weeks 1 to 2 for the HAESquestionnaire (ICC¼ 0.72, P< 0.0001), for the 3-dayactivity diary (ICC¼ 0.76, P< 0.0001), and for theaccelerometer (ICC¼ 0.63, P< 0.0001; see Table 5).

Additional analyses were performed on the results fromthe three instruments and reliability was assessed forthe time of day, weekday or weekend periods, andintensity levels. Significant reliability estimates wereobtained for the instruments in all categories except foraccelerometer activity counts in the somewhat activeintensity level (P¼ 0.08). These results are presented inTable 5.

TABLE 1— Descriptive Characteristics of the Study Population

Variable Combined (mean� SD) Females (mean� SD) Males (mean� SD) M vs. F

Age (years) 16.2� 4.2 16.9� 4.2 15.6� 4.9 P¼ 0.93

Height (cm) 159.3� 14.7 153.9� 9 164.7� 16.2 P¼ 0.05

Mass (kg) 49.9� 13.9 46.7� 12.3 53.1� 15.6 P¼ 0.34

Lean body mass (kg) 33.6� 8.9 30.4� 5.8 36.1� 10 P¼ 0.26

Forced vital capacity (% pred) 81.5� 14 80.1� 14.8 82.9� 14.2 P¼ 0.54

Forced expiratory volume in 1 sec (% pred) 74.1� 19.3 73� 22.9 75.3� 16.8 P¼ 0.62

Maximum voluntary ventilation (% pred) 101.1� 22.7 105� 21.5 97.3� 23.2 P¼ 0.87

VO2 at peak exercise (ml kg�1 min�1) 42.3� 11 36.3� 10.9 48.2� 7.3 P¼ 0.04

Ventilation at peak exercise (L min�1 BTPS) 81.1� 34.5 65.9� 24.7 96.4� 36 P¼ 0.05

mVE/MVV (ratio) 93.5� 15.9 91.9� 16.8 95.1� 14.8 P¼ 0.34

TABLE 2— Habitual Activity Estimation Scale Results: Activity Time at Different Intensities Results in Hours (Mean�SD)

Time of day (hours) Intensity

Weekday Weekend

Week 1 Week 2 Week 1 Week 2

Morning (A) Inactive 0.41� 1.14 0.27� 0.69 0.06� 0.19 0.08� 0.19

Somewhat inactive 1.71� 1.32 1.49� 1.32 0.83� 0.77 1.18� 1.19

Somewhat active 1.07� 1.02 0.73� 1.01 0.69� 1.04 1.63� 1.53

Active 0.56� 1.03 0.8� 1.27 0.66� 1.4 0.09� 0.27

Afternoon (B) Inactive 0.24� 0.44 0.26� 0.51 0.43� 1.15 0.07� 0.15


Somewhat active 1.67� 1.1 1.4� 0.83 2.69� 1.74 1.73� 1.28

Active 1.18� 1 1.29� 1.71 0.73� 1.32 0.46� 1.04

Evening (C) Inactive 0.57� 0.84 0.38� 0.8 0.16� 0.48 0.07� 0.16

Somewhat inactive 2.52� 1.34 1.51� 1.21 2.25� 1.26 2.23� 1

Somewhat active 0.6� 0.54 1.36� 1.34 0.85� 0.48 1.18� 1.3

Active 0.54� 1.34 0.79� 1.21 0.9� 1.75 0.49� 1.26

4 Wells et al.

Author Proof

AResults of the Validity Analysis

Significant positive correlations were detected betweenthe participants’ activity levels as estimated by the HAESand diary or HAES and accelerometer. Further, there weresignificant correlations between activity measures amongthe three instruments when broken into morning, after-noon, or evening periods, and between measuresfrom weekday or weekend days. There were significantcorrelations among the three instruments when recordingat different activity intensity levels (see Table 6), althoughthe HAES displays slightly lower agreement withaccelerometer data than the activity diary. Bland andAltman analysis comparing the results from the HAES,diary and accelerometer indicated that the 95% confidenceintervals were for the HAES versus diary�0.08–0.32, forthe HAES vs. the accelerometer 0.10–0.52, and for thediary versus accelerometer 0.05–0.38. The graphicalresults of the Bland and Altman results are presented inFigures 2–4.

DISCUSSION

The purpose of this study was to assess the reliabilityand validity of the Habitual Activation Scale question-naire in patients with CF. These findings suggest that theHAES questionnaire is a generally reliable and validinstrument that can be used to assess different activitylevels in patients with this disease. The findings of thisstudy are important as physical activity, and highintensity physical activity in particular, are importantfactors that are related to lung health,3 aerobiccapacity,9 and quality of life19 in this patient population.Further, the HAES is clinically feasible in that it is easyto administer and has a high compliance/completionrate. For example, measuring habitual physical activityin our entire clinic population (n ¼ 150) by instrumentssuch as pedometers and accelerometers is neitherfeasible nor possible. Previous experience has shownus that the compliance rate for the HAES is 100% whenthe subject completes a questionnaire on the same day it

TABLE 3— Activity Diary Results: Activity Time at Different Intensities Results in Hours (Mean�SD)

Time of day (hours) Intensity

Weekday Weekend


Morning (A) Inactive 0.07� 0.16 0.33� 1.09 0� 0 0� 0


Somewhat active 0.85� 0.92 1.06� 1.12 0.72� 0.7 1.33� 1

Active 0.6� 0.57 0.55� 0.76 0.8� 0.87 0.4� 0.52

Afternoon (B) Inactive 0.05� 0.15 0.02� 0.08 0� 0 0� 0


Somewhat active 1.49� 0.72 1.7� 1.05 1.91� 1.25 1.16� 1.04

Active 0.33� 0.28 0.67� 0.48 1.68� 1.8 1.05� 1.13

Evening (C) Inactive 0.28� 0.37 0.14� 0.29 0.01� 0.04 0� 0


Somewhat active 0.7� 0.33 0.56� 0.85 0.59� 0.93 0.7� 0.84

Active 0.95� 1.07 1.33� 1.27 0� 0 0.7� 0.9

TABLE 4— Accelerometer Results: Activity Time at Different Intensities Results in Hours (Mean�SD)

Time of day

(hours) Intensity

Weekday Weekend


Morning (A) Inactive 0.98� 0.92 0.84� 0.99 0.89� 1.19 0.5� 0.53


Somewhat active 0.53� 0.38 0.64� 0.4 0.5� 0.41 0.36� 0.47

Active 0.78� 0.65 1.2� 0.97 0.86� 0.64 0.81� 1.02

Afternoon (B) Inactive 1.15� 0.76 1.28� 0.72 1.03� 0.84 1.08� 1.2


Somewhat active 0.64� 0.36 0.68� 0.47 0.92� 0.7 0.64� 0.69

Active 1.28� 0.98 1.56� 1 1.89� 1.57 0.86� 0.82

Evening (C) Inactive 1.11� 0.77 0.96� 0.51 1.47� 0.79 1.03� 0.67

Somewhat inactive 0.85� 0.26 0.61� 0.35 1� 0.79 0.72� 0.57

Somewhat active 0.28� 0.2 0.44� 0.28 0.36� 0.28 0.47� 0.36

Active 0.9� 1.04 0.91� 1.02 0.75� 0.65 0.94� 0.88


Author Proof

Ais given where sending an instrument home (activitydiary or accelerometer) and waiting for it to be returnedhas been problematic. Therefore, the HAES can be usedfor clinical and research purposes to monitor activitylevels or changes in activity levels in response tospecific interventions thus potentially leading to a betterunderstanding of the determinants of health status in theCF population.

The results of the study suggest that the HAES, diaryand accelerometer have significant test–retest reliabilitywhen used to assess activity levels in patients with CF. The

reliability estimate obtained for the HAES instrument(ICC¼ 0.72), in this study was comparable to thereliability estimates for the modified Bratteby’s ActivityDiary (ICC¼ 0.78), and higher than that obtained foraccelerometer results (ICC¼ 0.636). The reliabilityestimates that were obtained for the HAES instrument inthe current research are consistent with results obtainedfor reliability estimates for the use of the HAES withschoolchildren.20 Therefore we conclude that the HAEScan be used to reliably assess activity levels in patientswith CF.

TABLE 5— Results of ICC Reliability Comparison for HAES (H), Activity Diary (D), and Accelerometer (A) Week 1 and Week 2Results

Validity comparison

HAES results Diary results Accelerometer results

ICC P-value ICC P-value ICC P-value

Week 1 vs. week 2 0.72 <0.0001 0.76 <0.0001 0.63 <0.0001

Morning week 1 vs. week 2 0.69 <0.0001 0.7 <0.0001 0.59 0.0001

Afternoon week 1 vs. week 2 0.71 <0.0001 0.8 <0.0001 0.55 0.0003

Evening week 1 vs. week 2 0.74 <0.0001 0.79 <0.0001 0.77 <0.0001

Weekday week 1 vs. week 2 0.75 <0.0001 0.89 <0.0001 0.74 <0.0001

Weekend week 1 vs. week 2 0.58 <0.0001 0.61 <0.0001 0.53 <0.0001

Inactive intensity week 1 vs. week 2 0.60 0.0001 0.38 0.03 0.81 <0.0001

Somewhat inactive intensity week 1 vs. week 2 0.67 <0.0001 0.46 0.005 0.38 0.04

Somewhat active intensity week 1 vs. week 2 0.55 0.0004 0.35 0.047 0.31 0.08

Active intensity week 1 vs. week 2 0.68 <0.0001 0.65 <0.0001 0.57 0.001

TABLE 6— Results of Intra-Class Correlation Coefficient Validity Analysis

Validity comparison Single measure ICC P-value

HAES vs. diary 0.58 <0.0001

HAES vs. accelerometer 0.44 <0.0001

Diary vs. accelerometer 0.59 <0.0001

HAES vs. diary morning 0.69 <0.0001

HAES vs. accelerometer morning 0.54 <0.0001

Diary vs. accelerometer morning 0.57 <0.0001

HAES vs. diary afternoon 0.41 0.0001

HAES vs. accelerometer afternoon 0.27 0.008

Diary vs. accelerometer afternoon 0.55 <0.0001

HAES vs. diary evening 0.67 <0.0001

HAES vs. accelerometer evening 0.51 <0.0001

Diary vs. accelerometer evening 0.66 <0.0001

HAES vs. diary weekday 0.62 <0.0001

HAES vs. accelerometer weekday 0.66 <0.0001

Diary vs. accelerometer weekday 0.63 <0.0001

HAES vs. diary weekend 0.54 <0.0001

HAES vs. accelerometer weekend 0.33 0.0002

Diary vs. accelerometer weekend 0.57 <0.0001

HAES vs. diary inactive and somewhat inactive 0.59 <0.0001

HAES vs. accelerometer inactive and somewhat inactive 0.40 0.0002

Diary vs. accelerometer inactive and somewhat inactive 0.42 <0.0001

HAES vs. diary somewhat active 0.29 0.004

HAES vs. accelerometer somewhat active 0.17 0.03

Diary vs. accelerometer somewhat active 0.33 0.0002

HAES vs. diary active 0.22 0.027

HAES vs. accelerometer active 0.38 0.0003

Diary vs. accelerometer active 0.51 <0.0001

6 Wells et al.

Author Proof

AThe patients in the current research had prior experiencein completing the HAES questionnaire and activity diary.While this likely improved the consistency of thereliability results in the current research, and is reflectiveof the typical results that would be obtained using theseinstruments as the subjects complete the HAES four times/year over a period of years, the reliability of the HAESinstrument as reported here may not apply to patients thatare inexperienced or new to activity assessment ques-tionnaires.

The results of the validity analysis suggest that therewere significant relationships between the activity levelsmeasured using the HAES and those obtained from theactivity diary and accelerometer, suggesting that theHAES is a generally valid instrument. This is supported by

the findings that results obtained using the HAES aresignificantly correlated with those obtained using anactivity diary that has been previously validated againstdoubly labeled water,11 or from a similar accelerometerthat has been previously validated against heart rate andenergy expenditure.17 Previous research has suggestedthat subjects typically over-report activity and higherintensity activities in particular.21 Similarly, the partic-ipants in the current research reported higher (non-significant) ‘‘somewhat inactive’’ (e.g., sitting) and higher(non-significant) ‘‘somewhat active’’ (e.g., walking)activities as assessed by the HAES and activity diarywhen compared to the accelerometer, although closeragreement was achieved at the ‘‘very active’’ (e.g.,running) intensity level. The significant associationsamong the instruments at the highest activity level isencouraging, especially in light of the recent article byHebestreit et al.9 who report that high levels of physicalactivity are associated with high aerobic capacity in CFpatients.

Interestingly, when the results of the HAES, activitydiary, and accelerometer were compared to the resultsfrom the accelerometer by activity level, the strength ofthe relationships were less than those found when makingother comparisons (see Table 6). This may be due toparticipants having difficulty remembering the exact timespent doing activities of lower intensity, while moreintense activities are easier to remember and report.However, these relationships were significantly correlatedacross all activity categories. This may be vital in CF asaerobic training and higher activity levels may beimportant in slowing the rate of decline of lung functionin this group.38

Accurate assessment of physical activity in CF iscritical for evaluation of the effectiveness of intervention

Fig. 2. Bland and Altman plot comparing the results from the

HAES instrument (H) to the activity diary (D). Units are number of

hours per category measured.


HAES instrument (H) to the accelerometer (A). Units are number

of hours per category measured.

COLOR


activity diary (D) to the accelerometer (A). Units are number of

hours per category measured.


Author Proof

Aprograms as well as for research on the impact of habitualactivity on health parameters. Physical activity has beenreported to have a positive impact on lung function in CFby (a) improving mucus clearance (22) and (b) having apositive impact on epithelial potential difference possi-bly leading to better mucus hydration.23 Unfortunately, ithas been reported that children with CF engaged in lessvigorous activity than their non-CF peers, despite goodlung function.24 In those patients with worse lungdisease, the amount of vigorous activity decreased withdecreasing FEV1. While the benefits of exercise trainingprograms have been demonstrated in CF,82526 thepositive results are generally short-term and difficult tomaintain, therefore changes in regular activity representa lifestyle modification which implies longer lastingbenefits.

The limitation of the current research is that it wasconducted using a relatively small number of participants,therefore the results should be interpreted carefully.Although the results of the current study suggest that theHAES is a generally reliable and valid instrument that canbe used to assess activities of varying intensity in patientswith CF, the sensitivity of the HAES to changes in activityremains to be established. The results of the currentresearch also highlights a major challenge for researchersand clinicians, that accurate measurement of habitualactivity is extremely difficult and a true criterion measureof physical activity outside of the laboratory has yet to bedeveloped. The moderate agreement that has been foundbetween the activity estimates obtained using the instru-ments in the current research highlights this challenge andsuggests that further research and efforts are required toclarify these measurements as physical activity remains anintervention with great potential for improving patienthealth in a variety of diseases.

CONCLUSIONS AND RECOMMENDATIONS

The findings of this study suggest that the HAESquestionnaire is a generally reliable and valid instrumentthat can be used to assess activity in patients with CF inadolescents and young adults. It is possible that theaccelerometer data collected for the inactive and some-what inactive categories may not be accurate, as themotion detector would not be able to distinguish betweenlying down and sitting, therefore this data should beinterpreted with caution. It is recommended that the‘‘inactive’’ (i.e., lying down) and ‘‘somewhat inactive’’(i.e., sitting) categories be merged into a single ‘‘inactive’’category for the CF population to increase the ease of useof the instrument and to allow for greater emphasis on the‘‘somewhat active’’ and ‘‘very active’’ levels of intensitythat have been shown to be related to improved lungfunction and aerobic capacity in CF patients.

ACKNOWLEDGMENTS

We are grateful to the Canadian CF Foundation and theIrwin Foundation at the Hospital for Sick Children Torontofor funding. Dr. Wells is supported by the Hospital for SickChildren Research Training Fellowship.

REFERENCES

1. Canadian Cystic Fibrosis Foundation. Canadian patient data

registry national report, 2002. 2004.

2. Selvadura HC, Blimkie CJ, Cooper PJ, Mellis CM, Van Asperen

PP. Gender differences in habitual activity in children with cystic

fibrosis. Arch Dis Child 2004;89:928–933.

3. Schneiderman-Walker J, Wilkes DL, Strug L, Lands LC, Pollock

SL, Selvadurai HC, et alQ3. Sex differences in habitual physical

activity and lung function decline in children with cystic fibrosis.

J Pediatr 2005;147:321–326.

4. Lands LC, Heigenhauser GJ, Jones NL. Analysis of factors

limiting maximal exercise performance in cystic fibrosis. Clin Sci

1992;83:391–397.

5. Coates AL, Boyce P, Muller D, Mearns M, Godfrey S. The role of

nutritional status, airway obstruction, hypoxia, and abnormalities

in serum lipid composition in limiting exercise tolerance in

children with cystic fibrosis. Acta Paediatr Scand 1980;69:353–

358.

6. Klijn PH, van der Net J, Kimpen JL, Helders PJ, van der Ent CK.

Longitudinal determinants of peak aerobic performance in

children with cystic fibrosis. Chest 2003;124:2215–2219.

7. Marcotte JE, Canny GJ, Grisdale R, Desmond K, Corey M,

Zinman R, et al. Effects of nutritional status on exercise

performance in advanced cystic fibrosis. Chest 1986;90:375–379.

8. Schneiderman-Walker J, Pollock SL, Corey M, Wilkes DD,

Canny GJ, Pedder L, et al. A randomized controlled trial of a 3-

year home exercise program in cystic fibrosis. J Pediatr

2000;136:304–310.

9. Hebestreit H, Keiser S, Rudiger S, et al. Physical activity is

independently related to aerobic capacity in cystic fibrosis. Eur

Respir J 2006;28:734–739.

10. Boucher GP, Lands LC, Hay JA, Hornby L. Activity levels and the

relationship to lung function and nutritional status in children

with cystic fibrosis. Am J Phys Med 1997;76:311–315.

11. Bratteby LE, Sandhagen B, Fan H, Samuelson G. A 7-day activity

diary for assessment of daily energy expenditure validated by the

doubly labelled water method in adolescents. Eur J Clin Nutr

1997;51:585–591.

12. Ekelund U, Sjostrom M, Yngve A, Poortvliet E, Nilsson A,

Froberg K, et al. Physical activity assessed by activity monitor

and doubly labelled water in children. Med Sci Sports Exerc

2001;33:275–281.

13. Hay JA, Cairney J. Development of the habitual activity

estimation scale for clinical research: a systematic approach.

Pediatr Exerc Sci 2006;18:193–202.

14. Bouchard C, Tremblay A, Leblanc C, Lortie G, Savard R,

Theriault G. A method to assess energy expenditure in children

and adults. Am J Clin Nutr 1983;37:461–467.

15. Sirard JR, Pate RR. Physical activity assessment in children and

adolescents. Sports Med 2001;31:439–454.

16. Wong SL, Leatherdale ST, Manske SR. Reliability and validity of

a school-based physical activity questionnaire. Med Sci Sports

Exerc 2006;38:1593–1600.

17. Trost SG, Ward DS, Moorehead SM, Watson PD, Riner W, Burke

JR. Validity of the computer science and applications (CSA)

activity monitor in children. Med Sci Sports Exerc 1998;30:629–

633.

8 Wells et al.

Author Proof

A18. Crouter SE, Clowers KG, Bassett DR. A novel method for using

accelerometer data to predict energy expenditure. J Appl Physiol

2006;100:1324–1331.

19. Orenstein DM, Nixon PA, Ross EA, Kaplan RM. The quality of

well-being in cystic fibrosis. Chest 1989;95:344–347.

20. Hay J, Atkinson S, Halton J. An examination of the reliability of

the habitual activity estimation scale (HAES). In: proceedings of

the Pediatric Work Physiology Symposium. 1995; 49.

21. Pitta F, Troosters T, Probst VA, Spruit MA, Decramer M, Gosselink

R. Quantifying physical activity in daily life with questionnaires

and motion sensors in COPD. Eur Respir J 2006;27:1040–1055.

22. Dinwiddie R. Diagnosis and management of paediatric respira-

tory disease. New York: Churchill Livingstone; 1997.

23. Hebestreit A, Kersting U, Basler B, Jeschke R, Hebstreit H.

Exercise inhibits epithelial sodium channels in patients with

cystic fibrosis. Am J Respir Crit Care Med 2001;164:443–446.

24. Nixon PA, Orenstein DM, Kelsey JL. Habitual physical activity in

children and adolescents with cystic fibrosis. Med Sci Sports

Exerc 2001;33:30–35.

25. Orenstein DM. Exercise conditioning and cardiopulmonary

fitness in cystic fibrosis: the effects of a 3-month supervised

running program. Chest 1981;80:392–398.

26. Stanghelle JK, Hjeltnes N, Bangstad H, Michalsen H. Effects of

daily short bouts of trampoline exercise during 8 weeks on the

pulmonary function and the maximal oxygen uptake of children

with cystic fibrosis. Int J Sports Med 1988;9:32–36.

Q1: Please check the affiliations.

Q2: Please check the placement of the inserted closing paren-

thesis.

Q3: Please provide the list of all the authors names for all et al.

references.


1 1 1 R I V E R S T R E E T, H O B O K E N, N J 0 7 0 3 0

ELECTRONIC PROOF CHECKLIST, P E D I A T R I C P U L M O N O L O G Y

***IMMEDIATE RESPONSE REQUIRED***Please follow these instructions to avoid delay of publication.

READ PROOFS CAREFULLY• This will be your only chance to review these proofs.• Please note that the volume and page numbers shown on the proofs are for position only.

ANSWER ALL QUERIES ON PROOFS (Queries for you to answer are attached as the last page of your proof.)• Mark all corrections directly on the proofs. Note that excessive author alterations may ultimately result in delay of

publication and extra costs may be charged to you.

CHECK FIGURES AND TABLES CAREFULLY (Color figures will be sent under separate cover.)• Check size, numbering, and orientation of figures.• All images in the PDF are downsampled (reduced to lower resolution and file size) to facilitate Internet delivery.

These images will appear at higher resolution and sharpness in the printed article.• Review figure legends to ensure that they are complete.• Check all tables. Review layout, title, and footnotes.

COMPLETE REPRINT ORDER FORM• Fill out the attached reprint order form. It is important to return the form even if you are not ordering reprints. You

may, if you wish, pay for the reprints with a credit card. Reprints will be mailed only after your article appears inprint. This is the most opportune time to order reprints. If you wait until after your article comes off press, thereprints will be considerably more expensive.

RETURN PROOFSREPRINT ORDER FORMCTA (If you have not already signed one)

RETURN WITHIN 48 HOURS OF RECEIPT VIA FAX TO Alyson Linefsky AT 201-748-6052

QUESTIONS? Alyson Linefsky, Senior Production EditorPhone: 201-748-6723E-mail: [email protected] to journal acronym and article production number(i.e., PPUL 00-001 (20000) for Pediatric Pulmonology ms 00-001).

111 River Street

201-748-6723FAX 201-748-6052

CCOOPPYYRRIIGGHHTT TTRRAANNSSFFEERR AAGGRREEEEMMEENNTT

Date:

To:

Production/ContributionID#______________Publisher/Editorial office use only

Re: Manuscript entitled___________________________________________________________________________________________________________________________________________________________________ (the "Contribution")

for publication in _____________________________________________________________________ (the "Journal")published by Wiley-Liss, Inc., a subsidiary of John Wiley & Sons, Inc. ( "Wiley").

Dear Contributor(s):

Thank you for submitting your Contribution for publication. In order to expedite the publishing process and enable Wiley todisseminate your work to the fullest extent, we need to have this Copyright Transfer Agreement signed and returned to us assoon as possible. If the Contribution is not accepted for publication this Agreement shall be null and void.

A. COPYRIGHT

1. The Contributor assigns to Wiley, during the full term of copyright and any extensions or renewals of that term, allcopyright in and to the Contribution, including but not limited to the right to publish, republish, transmit, sell,distribute and otherwise use the Contribution and the material contained therein in electronic and print editions ofthe Journal and in derivative works throughout the world, in all languages and in all media of expression nowknown or later developed, and to license or permit others to do so.

2. Reproduction, posting, transmission or other distribution or use of the Contribution or any material containedtherein, in any medium as permitted hereunder, requires a citation to the Journal and an appropriate credit to Wileyas Publisher, suitable in form and content as follows: (Title of Article, Author, Journal Title and Volume/IssueCopyright [year] Wiley-Liss, Inc. or copyright owner as specified in the Journal.)

B. RETAINED RIGHTS

Notwithstanding the above, the Contributor or, if applicable, the Contributor's Employer, retains all proprietary rightsother than copyright, such as patent rights, in any process, procedure or article of manufacture described in theContribution, and the right to make oral presentations of material from the Contribution.

C. OTHER RIGHTS OF CONTRIBUTOR

Wiley grants back to the Contributor the following:

1. The right to share with colleagues print or electronic "preprints" of the unpublished Contribution, in form andcontent as accepted by Wiley for publication in the Journal. Such preprints may be posted as electronic files on theContributor's own website for personal or professional use, or on the Contributor's internal university or corporatenetworks/intranet, or secure external website at the Contributor’s institution, but not for commercial sale or for anysystematic external distribution by a third party (e.g., a listserve or database connected to a public access server).Prior to publication, the Contributor must include the following notice on the preprint: "This is a preprint of anarticle accepted for publication in [Journal title] copyright (year) (copyright owner as specified in the Journal)".After publication of the Contribution by Wiley, the preprint notice should be amended to read as follows: "This is apreprint of an article published in [include the complete citation information for the final version of the Contributionas published in the print edition of the Journal]", and should provide an electronic link to the Journal's WWW site,located at the following Wiley URL: http://www.interscience.Wiley.com/. The Contributor agrees not to update thepreprint or replace it with the published version of the Contribution.

Hoboken, NJ 07030, USA

2. The right, without charge, to photocopy or to transmit online or to download, print out and distribute to a colleague acopy of the published Contribution in whole or in part, for the Contributor's personal or professional use, for theadvancement of scholarly or scientific research or study, or for corporate informational purposes in accordance withParagraph D.2 below.

3. The right to republish, without charge, in print format, all or part of the material from the published Contribution in

a book written or edited by the Contributor.

4. The right to use selected figures and tables, and selected text (up to 250 words, exclusive of the abstract) from theContribution, for the Contributor's own teaching purposes, or for incorporation within another work by theContributor that is made part of an edited work published (in print or electronic format) by a third party, or forpresentation in electronic format on an internal computer network or external website of the Contributor or theContributor's employer.

5. The right to include the Contribution in a compilation for classroom use (course packs) to be distributed to students

at the Contributor’s institution free of charge or to be stored in electronic format in datarooms for access by studentsat the Contributor’s institution as part of their course work (sometimes called “electronic reserve rooms”) and for in-house training programs at the Contributor’s employer.

D. CONTRIBUTIONS OWNED BY EMPLOYER

1. If the Contribution was written by the Contributor in the course of the Contributor's employment (as a "work-made-for-hire" in the course of employment), the Contribution is owned by the company/employer which must sign thisAgreement (in addition to the Contributor’s signature), in the space provided below. In such case, thecompany/employer hereby assigns to Wiley, during the full term of copyright, all copyright in and to theContribution for the full term of copyright throughout the world as specified in paragraph A above.

2. In addition to the rights specified as retained in paragraph B above and the rights granted back to the Contributorpursuant to paragraph C above, Wiley hereby grants back, without charge, to such company/employer, itssubsidiaries and divisions, the right to make copies of and distribute the published Contribution internally in printformat or electronically on the Company's internal network. Upon payment of the Publisher's reprint fee, theinstitution may distribute (but not resell) print copies of the published Contribution externally. Although copies somade shall not be available for individual re-sale, they may be included by the company/employer as part of aninformation package included with software or other products offered for sale or license. Posting of the publishedContribution by the institution on a public access website may only be done with Wiley's written permission, andpayment of any applicable fee(s).

E. GOVERNMENT CONTRACTS

In the case of a Contribution prepared under U.S. Government contract or grant, the U.S. Government may reproduce,without charge, all or portions of the Contribution and may authorize others to do so, for official U.S. Governmentpurposes only, if the U.S. Government contract or grant so requires. (U.S. Government Employees: see note at end).

F. COPYRIGHT NOTICE

The Contributor and the company/employer agree that any and all copies of the Contribution or any part thereofdistributed or posted by them in print or electronic format as permitted herein will include the notice of copyright asstipulated in the Journal and a full citation to the Journal as published by Wiley.

G. CONTRIBUTOR'S REPRESENTATIONS

The Contributor represents that the Contribution is the Contributor's original work. If the Contribution was preparedjointly, the Contributor agrees to inform the co-Contributors of the terms of this Agreement and to obtain their signatureto this Agreement or their written permission to sign on their behalf. The Contribution is submitted only to this Journaland has not been published before, except for "preprints" as permitted above. (If excerpts from copyrighted works ownedby third parties are included, the Contributor will obtain written permission from the copyright owners for all uses as setforth in Wiley's permissions form or in the Journal's Instructions for Contributors, and show credit to the sources in theContribution.) The Contributor also warrants that the Contribution contains no libelous or unlawful statements, does notinfringe on the rights or privacy of others, or contain material or instructions that might cause harm or injury.

CHECK ONE:_____________________________________ ______________________

[____]Contributor-owned work Contributor's signature Date

_____________________________________________________________Type or print name and title

_____________________________________ ______________________Co-contributor's signature Date

_____________________________________________________________Type or print name and title

ATTACH ADDITIONAL SIGNATURE PAGE AS NECESSARY

_____________________________________ ______________________[____]Company/Institution-owned work Company or Institution (Employer-for-Hire) Date

(made-for-hire in thecourse of employment) _____________________________________ ______________________

Authorized signature of Employer Date

[____]U.S. Government work

NNoottee ttoo UU..SS.. GGoovveerrnnmmeenntt EEmmppllooyyeeeess

A Contribution prepared by a U.S. federal government employee as part of the employee's official duties, or which is anofficial U.S. Government publication is called a "U.S. Government work," and is in the public domain in the United States. Insuch case, the employee may cross out Paragraph A.1 but must sign and return this Agreement. If the Contribution was notprepared as part of the employee's duties or is not an official U.S. Government publication, it is not a U.S. Government work.

[____]U.K. Government work (Crown Copyright)

Note to U.K. Government Employees

The rights in a Contribution prepared by an employee of a U.K. government department, agency or other Crown body as partof his/her official duties, or which is an official government publication, belong to the Crown. In such case, the Publisherwill forward the relevant form to the Employee for signature.

Pediatric PulmonologyJOHN WILEY & SONS, INC.1 1 1 R I V E R S T R E E T , H O B O K E N , N J 0 7 0 3 0

Telephone Number: 201 748-6723 • Facsimile Number: 201-748-6052

To: Alyson Linefsky

Company:

Phone: 201 748-6723

Fax: 201-748-6052

From:

Date:

Pages including thiscover page:

Message:

C1

REPRINT BILLING DEPARTMENT •• 111 RIVER STREET, HOBOKEN, NJ 07030PHONE: (201) 748-6723; FAX: (201) 748-6052

E-MAIL: [email protected] REPRINT ORDER FORM

Please complete this form even if you are not ordering reprints. This form MUST be returned with your corrected proofsand original manuscript. Your reprints will be shipped approximately 4 weeks after publication. Reprints ordered after printingwill be substantially more expensive.

JOURNAL Pediatric Pulmonology VOLUME ISSUE

TITLE OF MANUSCRIPT

MS. NO. NO. OF PAGES AUTHOR(S)

No. of Pages 100 Reprints 200 Reprints 300 Reprints 400 Reprints 500 Reprints$ $ $ $ $

1-4 336 501 694 890 10525-8 469 703 987 1251 14779-12 594 923 1234 1565 1850

13-16 714 1156 1527 1901 227317-20 794 1340 1775 2212 264821-24 911 1529 2031 2536 303725-28 1004 1707 2267 2828 338829-32 1108 1894 2515 3135 375533-36 1219 2092 2773 3456 414337-40 1329 2290 3033 3776 4528

**REPRINTS ARE ONLY AVAILABLE IN LOTS OF 100. IF YOU WISH TO ORDER MORE THAN 500 REPRINTS, PLEASE CONTACT OUR REPRINTSDEPARTMENT AT (201) 748-8867 FOR A PRICE QUOTE.

Please send me _____________________ reprints of the above article at $

Please add appropriate State and Local Tax (Tax Exempt No.____________________) $for United States orders only.

Please add 5% Postage and Handling $

TOTAL AMOUNT OF ORDER** $**International orders must be paid in currency and drawn on a U.S. bankPlease check one: Check enclosed Bill me Credit CardIf credit card order, charge to: American Express Visa MasterCard

Credit Card No Signature Exp. Date

BILL TO: SHIP TO: (Please, no P.O. Box numbers)Name Name

Institution Institution

Address Address

Purchase Order No. Phone Fax

E-mail

Softproofing for advanced Adobe Acrobat Users - NOTES toolNOTE: ACROBAT READER FROM THE INTERNET DOES NOT CONTAIN THE NOTES TOOL USED IN THIS PROCEDURE.

Acrobat annotation tools can be very useful for indicating changes to the PDF proof of your article.By using Acrobat annotation tools, a full digital pathway can be maintained for your page proofs.

The NOTES annotation tool can be used with either Adobe Acrobat 4.0, 5.0 or 6.0. Other annotation tools are also available in Acrobat 4.0, but this instruction sheet will concentrateon how to use the NOTES tool. Acrobat Reader, the free Internet download software from Adobe,DOES NOT contain the NOTES tool. In order to softproof using the NOTES tool you must havethe full software suite Adobe Acrobat 4.0, 5.0 or 6.0 installed on your computer.

Steps for Softproofing using Adobe Acrobat NOTES tool:

1. Open the PDF page proof of your article using either Adobe Acrobat 4.0, 5.0 or 6.0. Proofyour article on-screen or print a copy for markup of changes.

2. Go to File/Preferences/Annotations (in Acrobat 4.0) or Document/Add a Comment (in Acrobat6.0 and enter your name into the “default user” or “author” field. Also, set the font size at 9 or 10point.

3. When you have decided on the corrections to your article, select the NOTES tool from theAcrobat toolbox and click in the margin next to the text to be changed.

4. Enter your corrections into the NOTES text box window. Be sure to clearly indicate where thecorrection is to be placed and what text it will effect. If necessary to avoid confusion, you canuse your TEXT SELECTION tool to copy the text to be corrected and paste it into the NOTEStext box window. At this point, you can type the corrections directly into the NOTES textbox window. DO NOT correct the text by typing directly on the PDF page.

5. Go through your entire article using the NOTES tool as described in Step 4.

6. When you have completed the corrections to your article, go to File/Export/Annotations (inAcrobat 4.0) or Document/Add a Comment (in Acrobat 6.0).

7. When closing your article PDF be sure NOT to save changes to original file.

8. To make changes to a NOTES file you have exported, simply re-open the original PDFproof file, go to File/Import/Notes and import the NOTES file you saved. Make changes and re-export NOTES file keeping the same file name.

9. When complete, attach your NOTES file to a reply e-mail message. Be sure to include yourname, the date, and the title of the journal your article will be printed in.

Documents

Reliability and validity of the habitual activity estimation scale (HAES) in patients with cystic fibrosis