TOWARDS STANDARDIZED GLOBAL ASSESSMENT OF HEATLH-RELATED PHYSICAL ACTIVITY - THE INTERNATIONAL PHYSICAL ACTIVITY QUESTIONNAIRES (IPAQ)

Abstract

PURPOSE: Physical inactivity is a global public health issue. However, the scope of the problem is difficult to gauge. While a number of countries assess physical activity as part of national health surveys, they use a variety of definitions and questionnaires. In order to better assess the risk of physical inactivity at a national, regional and global level a greater degree of standardization in definitions and assessment is required. The aim of this study was to develop a set of questionnaires for use in population-based national surveys to assess health-related physical activity in a comparable manner across countries. METHODS: After extensive question development, pilot testing, and revision, 8 questionnaires were tested for reliability and validity in 14 centers in 12 countries on 6 continents. The 8 questionnaires included both long and short versions, which were divided by mode of administration (telephone or self-complete) and the reference period recalled (usual week or past 7 days). Repeatability, was assessed within the same week. Concurrent (intermethod) validity was assessed within the same day and criterion validity was assessed against the CSA accelerometer. Spearmans correlation coefficients are reported, based on the total reported physical activity. RESULTS: Overall, the IPAQ questionnaires produced repeatable data (Spearmans Rho clustered around 0.8), with comparable data from short and long forms. The short form appeared to account for all aspects of physical activity when compared to the long form. Criterion validity had a median of about rho = .39, that was comparable to other self-report validation studies. The “usual week” and “last 7 days” reference periods performed similarly well, and the reliability of telephone administration was similar to the self-administered mode. CONCLUSIONS: Our results demonstrate that the IPAQ instruments have measurement properties comparable to other established self report instruments. Considering the international and diverse samples used in this study the IPAQ instruments are recommended as the preferred method of monitoring population levels of heal-related physical activity for middle-aged adults. The short form of the “last 7 days” recall is recommended for national monitoring and surveillance systems, and the long form of the “last 7 days” recall is recommended for research purposes.