Journal of Science and Medicine in Sport (2006) 9, 319—326 ORIGINAL PAPER Measurement properties of the CHAMPS physical activity questionnaire in a sample of older Australians E.V. Cyarto ∗, A.L. Marshall, R.K. Dickinson, W.J. Brown School of Human Movement Studies, The University of Queensland, St. Lucia, Brisbane, Qld. 4072, Australia Received 15 October 2005 ; received in revised form 17 February 2006; accepted 5 March 2006 KEYWORDS Physical activity measurement; Elderly; Reliability; Predictive validity Summary Background: The effective evaluation of physical activity interventions for older adults requires measurement instruments with acceptable psychometric properties that are sufficiently sensitive to detect changes in this population. Aim: To assess the measurement properties (reliability and validity) of the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire in a sample of older Australians. Methods: CHAMPS data were collected from 167 older adults (mean age 79.1 S.D. 6.3 years) and validated with tests of physical ability and the SF-12 measures of physical and mental health. Responses from a sub-sample of 43 older adults were used to assess 1-week test—retest reliability. Results: Approximately 25% of participants needed assistance to complete the CHAMPS questionnaire. There were low but significant correlations between the CHAMPS scores and the physical performance measures (rho = 0.14—0.32) and the physical health scale of the SF-12 (rho = 0.12—0.24). Reliability coefficients were highest for moderate-intensity (ICC = 0.81—0.88) and lowest for vigorous-intensity physical activity (ICC = 0.34—0.45). Agreement between test-retest estimates of sufficient physical activity for health benefits (≥150 min and ≥5 sessions per week) was high (percent agreement = 88% and Cohen’s kappa = 0.68). Conclusion: These findings suggest that the CHAMPS questionnaire has acceptable measurement properties, and is therefore suitable for use among older Australian adults, as long as adequate assistance is provided during administration. © 2006 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved. Introduction ∗ Corresponding author. E-mail address: ecyarto@hms.uq.edu.au (E.V. Cyarto). The number of Australians aged over 65 years and, consequently, the number of people with chronic disease and/or age-related disorders is set 1440-2440/$ — see front matter © 2006 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.jsams.2006.03.001 320 to rapidly increase over the next 20 years.1 Regular physical activity (PA) can prevent or postpone the development of many chronic health conditions, and in older adults it can ameliorate the declines in physical function commonly associated with ageing.2—4 To prevent the course of unhealthy ageing, research attention is beginning to focus on the development and implementation of strategies for increasing PA among older adults. To enhance the evidence base, programs must be rigorously evaluated. Measurement tools that provide valid and reliable estimates of PA in this population need to be identified. In applied research settings, PA is usually assessed using self-report methods (e.g. survey and diaries). Population-based data collected using the Active Australia (AA) questionnaire suggest that only 44% of Australian adults aged 60—75 years are sufficiently active for health benefit and that almost one in five older Australians are completely sedentary.5 The reliability and validity of the AA questionnaire have been established6,7 but were found to be lowest among those aged over 60 years.6 Whilst the AA questionnaire is the preferred instrument for monitoring national population levels of PA over time, it may not be sensitive enough to detect small but significant changes in PA following planned interventions in smaller samples of older Australians. Self-report data are limited by a number of factors. Among older adults in particular, selfreport data may be plagued by recall bias8,9 and by the ‘floor’ effects resulting from low levels of PA in this population.8,10 To address these issues, several PA questionnaires have been developed overseas to assist older adults recall and report PA.11—15 Typically, these surveys emphasise leisure and household activities, although the Physical Activity Scale for the Elderly (PASE)14 and the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire15 also measure time spent in paid or volunteer work. Within leisure and household domains, the PASE, the Yale Physical Activity Survey (YPAS),13 and the CHAMPS questionnaire15 cover the widest spectrum of activities. In terms of capturing small changes in PA over time, the CHAMPS questionnaire has been found to be more sensitive to change than the YPAS or the PASE.8 Stewart and colleagues15 developed the CHAMPS questionnaire as an outcome measure for a PA intervention study, because, at that time there were no accurate self-report instruments for assessing PA in under-active older adults. The questionnaire was specifically designed to minimise social desirability (by including non-physical activities such as hob- E.V. Cyarto et al. bies) and recall bias (use of recognition memory). The CHAMPS questionnaire assesses the weekly frequency and duration of activities typically undertaken by older adults at light (e.g. leisurely walking, light gardening), moderate (e.g. cycling, heavy housework) and vigorous (e.g. singles tennis, jogging) intensities. A MET value is assigned to each activity, using the compendium,16 but with adjustment for the likely intensity of each activity among older adults.15 To date, two studies have evaluated the psychometric properties of the CHAMPS questionnaire among community-dwelling older adults in the United States. They reported Intraclass Correlation Coefficients (ICC) with moderate 6-month stability (ICC = 0.58—0.67)15 and good test-retest reliability over a 2-week period (ICC = 0.62—0.76).8 In these studies, the CHAMPS data demonstrated modest but acceptable predictive validity, including associations between CHAMPS scores and both physical functioning and health-related quality of life measures.8 CHAMPS data also showed moderate correlations with data from the PASE and the YPAS,8 and were able to discriminate between less active and more active older adults.8,15 To date, no studies have explored the measurement properties of the CHAMPS survey in older Australian adults. The aim of the present study was therefore to examine the predictive validity and test-retest reliability of the CHAMPS questionnaire in a sample of older Australians. Methods Participants A sample of 167 older adults (132 women and 35 men) aged over 60 years was recruited from nine independent-living retirement villages located in the Brisbane metropolitan area. These residents had volunteered to participate in an exercise program, due to commence at the completion of this study. Participants were provided with verbal and written information about the project, and informed consent forms were signed prior to participation. Approval for this study was obtained from the Medical Research Ethics Committee at The University of Queensland. Procedures Standard demographic and health-related questions and the short self-report measure of health status (SF-12)17 were completed up to 1 week in advance of the first functional assessment session Measurement properties of the CHAMPS physical activity questionnaire (T1). At T1 participants completed three components of the Senior Fitness Test18 (chair stand for lower body strength, 8-ft ‘up and go’ for agility, and step test for aerobic endurance) and a balance test.19 Immediately following these tests, they completed the CHAMPS questionnaire in small groups. A research assistant was available to assist participants who experienced difficulty reading or understanding the written instructions. The CHAMPS questionnaire asked participants to recall the weekly frequency and duration of each activity included in a comprehensive list of light-, moderate- and vigorous-intensity activities. Participants were asked to recall their activities in ‘a typical week over the last 4 weeks’. Consistent with the methods used by Harada et al.8 and Stewart et al.15 , data from the four physical performance tests and SF-12 were compared with the self-reported CHAMPS data to assess the predictive validity of the survey. The specific hypotheses were: (1) the CHAMPS scores would positively correlate with the physical performance test Table 1 321 scores; and (2) higher correlations would be found between CHAMPS scores and the physical component summary score of the SF-12 than between CHAMPS scores and the mental component summary score. To assess test-retest reliability, participants from three of the villages (43 women and 13 men) volunteered to complete a second questionnaire 1 week later (T2) and return it to the investigators via a dedicated ‘post box’ located in a common area of their village. Data analysis The sum of the products of weekly frequency and duration (hours) of PA were computed to determine the ‘volume’ (MET.hours) of activities categorised as light- (≥2 MET but <3 MET), moderate- (≥3 MET but <6 MET) and vigorous-intensity (≥6 MET). The MET classifications were the same as those used by Stewart and colleagues.15 Spearman’s rank correlation coefficients were calculated to examine predictive validity (comparing the CHAMPS scores with the physical performance tests and with the Demographic, health and physical activity characteristics of the participants Mean (S.D.) Age (years) Prescribed medications Validity study (N = 167) Reliability study (N = 43) 79.1 (6.3) 3.9 (2.7) 77.4 (6.6)* 3.8 (2.5) Validity study (N = 167) Reliability study (N = 43) 79.0 98.2 34.7 72.1 100.0 41.9 Education Higher school or less Trade or diploma University degree Employment status (retired) 77.8 17.4 4.8 85.0 74.4 21.0 4.7 83.7 Self-reported medical conditions Arthritis Hypertension Elevated cholesterol level Cardiovascular problems Diabetes Osteoporosis 55.1 46.1 36.5 22.8 11.4 33.5 51.2 46.5 32.6 25.6 11.6 20.9* Physical activity Sufficient activity times and sessionsa Insufficient activity times and sessions Sedentary (N = 164) 15.9 82.3 1.8 Percentage Gender (female) Ethnicity (Caucasian) Marital status (married) (N = 41) 26.8* 73.2* 0 a Sufficient activity time and sessions is defined as at least 150 min in at least five sessions of moderate-intensity activity per week.3 * Significant difference between validity study and reliability study participants (p < 0.05). 322 E.V. Cyarto et al. SF-12 scores). After performing logarithmic and square root transformations to normalise skewed data, ICCs were used to assess test-retest reliability (comparing scores at T1 and T2). Measures of weekly frequency and volume of PA were used to categorise participants’ activity level based on current Australian guidelines.3 Participants were classified as ‘sufficiently active’ if they reported ≥150 min and ≥5 sessions of weekly PA of at least moderate-intensity and ‘insufficiently active’ if they did not. Percent agreement and Cohen’s kappa20 were used to assess the reliability of the classification between T1 and T2. Correlation coefficients ≥0.75 indicated excellent reliability and the magnitude of the kappa value was classified as poor to slight (0—0.20), fair (0.21—0.40), moderate (0.41—0.60), substantial (0.61—0.80), or almost perfect (0.81—1.00).21 For all analyses, significance was set at an alpha level of p < 0.05. Data were analysed using the Statistical Package for the Social Sciences (SPSS), version 13.0. Results Complete predictive validity and test-retest reliability data were received from 167 and 43 participants, respectively. Participants were aged between 65 and 96 years. The majority of participants were retired women, and 72% reported three or more chronic health problems. The reliability sample was significantly younger, included fewer participants with osteoporosis, and included more participants classified as sufficiently active than the validity sample (see Table 1). Thirteen of those who volunteered to participate in the reliability study did not complete the CHAMPS questionnaire at T2. There were no significant differences in demographic or health characteristics between those who did and those who did not complete the survey a second time. Despite providing detailed written instructions for completion and an example to follow, approximately 25% of participants needed assistance to complete the CHAMPS survey at T1. The most common survey completion error was that participants (n = 7) circled the total hours spent in a particular activity but did not write a response for the frequency of participation. Although most participants took at least 15 min to complete the CHAMPS questionnaire, some took considerably longer (up to 30 min). The last item in the CHAMPS questionnaire allowed respondents to specify additional type(s) of PA (not included in the list). The additional activities reported were: table tennis (n = 5), carpet/indoor bowls (n = 4), lawn bowls (n = 3), and pushing a wheelchair (n = 1). Using the compendium as a guide,16 these activities were assigned a MET value of 3.0, with the exception of carpet/indoor bowls which was categorised as a light-intensity activity (2.5 MET). The CHAMPS data were significantly skewed, thus Medians and Inter Quartile Ranges (IQR) are reported in Tables 2 and 3. The numbers included in each analysis vary because not all participants provided complete frequency data for all the items in the validity (n = 7) and reliability analyses (n = 4). In a typical week over the previous 4 weeks, participants in both sets of analyses engaged most frequently in light-intensity activities. In the pre- Table 2 CHAMPS physical activity measures: descriptive statistics and correlations (Spearman’s Rho) with physical performance tests and self reported physical and mental well-being (N = 167) CHAMPS output Median IQR a Spearman’s Rho Chair stand Step test 8-ft up & go Tandem balance SF-12 physical SF-12 mental Moderate + vigorous-intensity PA (MET ≥ 3.0) MET.hours per week 3.0 10.7 Frequency per weekb 2.0 5.0 0.19* 0.16* 0.32*** 0.31*** 0.31*** 0.29*** 0.31*** 0.28*** 0.18* 0.12 −0.14 −0.11 All activities MET.hours per week Frequency per weekc 0.21** 0.14 0.28*** 0.26** 0.28*** 0.28*** 0.29*** 0.23** 0.24** 0.15 −0.14 −0.09 a b c * ** *** IQR—–interquartile range. N = 164. N = 160. p ≤ 0.05. p ≤ 0.01. p ≤ 0.001. 19.8 14.0 23.4 13.8 Descriptive profile and 1-week test-retest reliability of the physical activity outcomes derived from the CHAMPS questionnaire (N = 43) CHAMPS outcomes (Time 1) CHAMPS outcomes (Time 2) ICCc 95% CI p< Mean (S.D.)a Median IQRb Hours per week Light-intensity Moderate-intensity PA Vigorous-intensity PA Moderate + vigorous-intensity PA All activities 8.3 3.2 0.8 4.0 12.3 (5.9) (5.3) (1.6) (6.0) (10.1) 7.0 0.5 0 1.5 10.5 8.0 5.0 0.5 5.0 11.0 7.1 2.0 0.3 2.3 9.4 (4.3) (2.5) (0.5) (2.7) (5.7) 6.0 0.5 0 1.0 8.5 6.0 3.5 0.5 4.0 7.5 0.67 0.85 0.34 0.78 0.76 0.47—0.81 0.74—0.92 0.05—0.58 0.63—0.87 0.60—0.86 0.0001 0.0001 0.05 0.0001 0.0001 Frequency per week Light-intensityd Moderate-intensity PAe Vigorous-intensity PA Moderate + vigorous-intensity PAe All activitiesd 11.9 2.9 2.1 5.1 17.2 (7.1) (4.0) (2.7) (5.2) (10.3) 10.0 1.0 0 4.0 16.0 10.0 5.5 4.0 8.0 13.0 11.5 2.6 1.2 3.7 15.4 (6.4) (3.5) (2.2) (4.5) (9.8) 11.0 1.0 0 3.0 13.0 9.0 4.0 2.0 6.0 10.0 0.65 0.81 0.45 0.76 0.79 0.43—0.90 0.68—0.90 0.18—0.66 0.59—0.86 0.64—0.87 0.0001 0.0001 0.001 0.0001 0.0001 Volume (MET.hours per week) Light-intensity Moderate-intensity PA Vigorous-intensity PA Moderate + vigorous-intensity PA All activities 19.8 11.4 5.0 16.4 36.3 (14.2) (18.8) (9.7) (23.4) (32.3) 15.1 2.0 0 6.3 29.6 18.9 17.3 3.0 23.0 33.0 17.1 7.1 1.7 8.9 26.0 (10.3) (9.3) (3.2) (10.4) (16.9) 14.1 1.8 0 4.8 24.4 13.3 12.3 3.0 15.3 19.0 0.66 0.88 0.44 0.76 0.75 0.46—0.80 0.79—0.93 0.17—0.65 0.61—0.87 0.58—0.86 0.0001 0.0001 0.001 0.0001 0.0001 a b c d e Mean (S.D.) Median IQR Measurement properties of the CHAMPS physical activity questionnaire Table 3 S.D.—–standard deviation. IQR—–interquartile range. ICC—–intraclass correlation coefficient. N = 39. N = 41. 323 324 E.V. Cyarto et al. Table 4 Proportion of participants meeting the Australian physical activity guidelines (at least 150 min in at least five sessions of moderate-intensity physical activity per week) and consistency of classification between T1 and T2 (N = 41) T1 T2 Sufficiently active (%) Insufficiently active (%) Sufficiently active Insufficiently active 8 (19.5) 2 (4.9) 3 (7.3) 28 (68.3) dictive validity sample, median measures of total frequency and volume of weekly activities were approximately seven times greater than those for moderate- and vigorous-intensity PA. As hypothesised, significant, positive correlations were found between the CHAMPS scores and the performancebased functional measures, although the magnitude of the rho values was only fair (see Table 2). Also as anticipated, there were stronger correlations with the physical component summary score of the SF-12 than with the mental component summary score. The sub-sample of participants who provided test-retest reliability data also reported predominantly light-intensity activities and very few reported any vigorous-intensity PA (see Table 3). The median values at T1 were slightly higher than at T2 for most measures. For hours per week, frequency per week, and MET.hours per week, 1-week test-retest reliability was highest for the moderateintensity measures, ranging from ICC = 0.81 to 0.88, and lowest for the vigorous-intensity measures (ICC = 0.34—0.45). All ICCs, except those for the vigorous-intensity measures, could be considered moderate to excellent. Only 11 (26%) of the 41 participants who provided complete data at T1, and 10 (24%) at T2, were classified as sufficiently active. The percent agreement and Cohen’s kappa statistics indicate a substantial level of agreement in categorisation of participants between T1 and T2 (see Table 4). Discussion This study examined the measurement properties (predictive validity and test-retest reliability) of the CHAMPS questionnaire, to determine its suitability for use with older Australians. To date, the psychometric properties of this questionnaire have only been evaluated with samples of older Americans.8,15 In this study, the length of time required to complete the CHAMPS questionnaire was comparable to previous reports involving samples of communitydwelling older adults.8,15 However, approximately Percent agreement Kappa p 87.8 0.68 <0.001 one quarter of the participants required interviewer assistance and several provided incomplete data. As previous researchers have not noted this problem, we assume that it reflects the lower education levels of this Australian sample, 80% of whom had no more than a high school education, compared with only 15% in the study by Stewart et al.15 . Moreover, 12 of the 13 non-completers in the reliability study had no post-school qualifications. Thus, in its present form, the length and complexity of the CHAMPS questionnaire may have made completing the questionnaire too cumbersome for some individuals in this study. Further exploration of ways to enhance the use of this questionnaire for self-reporting PA in Australian samples is therefore warranted. For the most part, the activities included in the CHAMPS questionnaire are meaningful and appropriate for Australian older adults. However, due to differences in climate between North America and Australia, many of the Australians commented that they had never skated, and several reported regularly playing lawn or carpet bowls in the ‘other activity’ question. As up to 9% of Australians over the age of 65 years participate in lawn or carpet bowls (only walking had a higher rate of participation in a recent national survey22 ), it will be important to include this activity if the CHAMPS questionnaire is to be used more widely in Australia. This study provides additional support for the predictive validity of the CHAMPS questionnaire and both hypotheses were confirmed. Harada and colleagues8 and Stewart and colleagues15 used the Short Physical Performance Battery23 to provide a measure of lower body functioning (summary score comprising strength, balance and walking) and the 6-min walk to determine aerobic endurance. The correlations reported in our study (rho = 0.19—0.32) were more closely aligned with those reported by Stewart et al.15 (r = 0.22—0.28) than with those reported by Harada et al.8 (r = 0.39—0.54). The self-report SF-3624 was used to measure health-related quality of life in the two previous assessments of the CHAMPS questionnaire.8,15 In contrast, participants in this study completed Measurement properties of the CHAMPS physical activity questionnaire the SF-12,17 which has been shown to have good validity against the SF-36.25 Across all three studies, as expected, the relationship between CHAMPS outcomes and physical functioning measures was stronger than with the mental health measures. In the present study, the reliability coefficients were higher than those reported in previous studies. For example, in this study the ICC was 0.75 for total volume of all activities compared with 0.62 and 0.66, respectively, in the studies reported by Harada et al.8 and Stewart et al.15 . One likely explanation is that the test-retest timeframe was 1 week in this study compared with 2 weeks8 and 6 months15 in the previous studies. In the design of contemporary reliability studies,6,7,26 an attempt is made to match the two recall periods as closely as possible without allowing the possibility of recall of responses. Unlike other measurement research studies,6,26 participants in this study tended to report less activity at T2 compared with T1. This may be partly explained by the fact that at T1 some participants may have been helped by the research assistant, but when completing the CHAMPS questionnaire independently at T2, these participants may have under-reported their PA. Unique to this study, the CHAMPS data were used to determine whether participants were meeting the current Australian PA guidelines.3 Surprisingly, only one in four participants in the reliability sample were categorised as sufficiently active (meeting guidelines) at T1. However, the reliability statistics indicate substantial agreement over the test-retest period suggesting that CHAMPS can consistently identify participants who are meeting the guidelines. These results compare favourably with the degree of consistency found in reliability studies of other PA questionnaires. For example, the percent agreement score for this study is well within the range reported by Craig and colleagues26 for the International Physical Activity Questionnaire (IPAQ, 77—100%). In an evaluation of four PA measures (AA survey, the short IPAQ and the physical activity items in the Behavioral Risk Factor Surveillance System and in the Australian National Health Survey), Brown and colleagues6 reported percent agreement and kappa statistics ranging from 60% to 79% and 0.40 to 0.52, respectively, which are lower than the corresponding values reported here for the CHAMPS questionnaire. There are two main limitations which should be considered when interpreting the findings of this study. Firstly, the participants were a convenience sample of older adults living in retirement villages who had volunteered to participate in an exercise intervention study. They may not therefore be representative of all older Australian adults. Sec- 325 ondly, the MET values assigned to each activity were obtained from Stewart and colleagues15 who modified the MET values identified in the compendium16 which were based on assessments of younger individuals. Until specific MET values are available for older adults, it will not be possible to accurately define what constitutes light-, moderate- or vigorous-intensity activity in this age group. Based on the findings of this study, the recommendation made by Stewart et al.15 about having someone available to provide assistance to respondents completing the CHAMPS questionnaire, is strongly advised. In addition, completed questionnaires should be thoroughly reviewed at the time of administration to minimise the amount of missing data. It may also be easier for participants to follow the instructions if a simple, daily activity (such as reading) is used as an example to follow, instead of the one used by Stewart et al.15 (visiting with friends or family). If problems with self-completion are anticipated in the target population and it is not feasible to have on-site support for respondents, telephone-administration of the CHAMPS survey may be a viable alternative. In summary, the findings of this study are consistent with those reported previously and support the use of CHAMPS as a measure of PA among older Australian adults. In particular, CHAMPS data may be used to identify those older adults who are insufficiently active for health benefit and are most in need of PA intervention. Further examination of the measurement properties of the CHAMPS questionnaire with more diverse samples of older adults is recommended. Practical implications • The Community Healthy Activity Model Programs for Seniors (CHAMPS) questionnaire can reliably measure the physical activity level of older Australians. • CHAMPS can be used to identify older adults who do not meet the national physical activity guidelines. • It is strongly recommended to have someone available to help respondents complete the questionnaire and check for missing data. Acknowledgements This project was funded by the Australian Government (Department of Health and Ageing—–Office for an Ageing Australia) and Blue Care (Uniting 326 Care Queensland). This research was carried out whilst Ms Cyarto was holding an International Postgraduate Research Scholarship at The University of Queensland. The authors wish to acknowledge the individuals who took part in this study. References 1. Australian Bureau of Statistics. 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