Methodological issues in surveys of physical activity: the case of the Trent Health Lifestyle Survey

This paper examines methodological issues in physical activity measure ment by examining the findings of the 1994 Trent Health Lifestyle Survey which reported physical activity participation levels in adult men and women in the Trent region of England. In the survey, individuals were sampled from FHSA registers across ten districts of Trent Regional Health Authority ( N=18,787), and results indicated that high proportions of males (44 per cent) and females (46 per cent) had not undertaken any occasions of moderate or vigorous physical activity of at least 20 minutes duration in the previous four weeks. When asked about accumulated time spent on physical activity, 65 per cent of males and 64 per cent of females reported participating in 30 minutes or more 'energetic' activity on most days. In order to examine methodological issues, results of the survey are compared with those from national physical activity prevalence surveys. This comparison illustrates that even small methodological differences between surveys can substantially influence results, and caution is required in making such comparisons.