Measurement properties of the CHAMPS physical activity questionnaire in a sample of older Australians

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. (c) 2006 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Relative validity of food intake estimates using a food frequency questionnaire is associated with sex, age, and other personal characteristics

We invostigated the validity of food intake estimates obtained by a self-administered FFQ relative to weighed food records (WFR) and the extent to which demographic, anthropometric, and social characteristics explain differences between these methods. A community-based sample of 96 Australian adults completed a FFQ and 12 d of WFR over 12 mo. The FFQ was adapted to the Australian setting from the questionnaire used in the US Nurses' Health Study. Spearman rank correlation coefficients ranged from 0.08 for other vegetables to 0.88 for tea. Exact agreement by quartiles of intake ranged from 27% (eggs) to 63% (tea). Differences between FFQ and WFR regressed on personal characteristics were significantly associated with at least 1 characteristic for 20 of the 37 foods. Sex was significantly associated with differences for 17 food groups, including 5 specific vegetable groups and 2 total fruit and vegetable groups. Use of dietary supplements and the presence of a medical condition were associated with differences for 5 foods; age, school leaving age, and occupation were associated with differences for 1-3 foods. BMI was rot associated with differences for any foods. Regression models explained from 3% (wholemeal bread) to 37% (for all cereals and products) of variation in differences between methods. We conclude that the relative validity of intake estimates obtained by FFQ is different for men and women for a large number of foods. These results highlight the need for appropriate adjustment of diet-disease relations for factors affecting the validity of food intake estimates.

The effect of personal characteristics on the validity of nutrient intake estimates using a food-frequency questionnaire

Objective: To assess validity of the Nambour food-frequency questionnaire (FFQ) relative to weighed food records (WFRs), and the extent to which selected demographic, anthropometric and social characteristics explain differences between the two dietary methods. Design: Inter-method validity study; 129-item FFQ vs. 12 days of WFR over 12 months. Setting: Community-based Nambour Skin Cancer Prevention Trial. Subjects: One hundred and fifteen of 168 randomly selected participants in the trial (68% acceptance rate) aged 25-75 years. Results: Spearman correlations between intakes from the two methods ranged from 0.18 to 0.71 for energy-adjusted values. Differences between FFQ and WFR regressed on personal characteristics were significantly associated with at least one characteristic for 16 of the 21 nutrients. Sex was significantly associated with differences for nine nutrients; body mass index (BMI), presence of any medical condition and age were each significantly associated with differences for three to six nutrients; use of dietary supplements and occupation were associated with differences for one nutrient each. There was no consistency in the direction of the significant associations. Regression models explained from 7% (riboflavin) to 27% (saturated fat) of variation in differences in intakes. Conclusions: The relative validity of FFQ estimates for many nutrients is quite different for males than for females. Age, BMI, medical condition and level of intake were also associated with relative validity for some nutrients, resulting in the need to adjust intakes estimates for these in modelling diet-disease relationships. Estimates for cholesterol, beta-carotene equivalents, retinol equivalents, thiamine, riboflavin and calcium would not benefit from this.

Translation and validation of the Chinese version of the Charing Cross Venous Ulcer Questionnaire

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A state-of-practice questionnaire on verification and validation for concurrent programs

Research in verification and validation (V&V) for concurrent programs can be guided by practitioner information. A survey was therefore run to gain state-of-practice information in this context. The survey presented in this paper collected state-of-practice information on V&V technology in concurrency from 35 respondents. The results of the survey can help refine existing V&V technology by providing a better understanding of the context of V&V technology usage. Responses to questions regarding the motivation for selecting V&V technologies can help refine a systematic approach to V&V technology selection.