Validity and reliability of a physical activity/inactivity questionnaire in South African primary schoolgirls

Abstract

Objective. We sought to determine the validity and reliability of a self-report physical activity questionnaire (PAQ) measuring physical activity/inactivity in South African schoolgirls of different ethnic origins. Methods. Construct validity of the PAQ was tested against physical activity energy expenditure estimated from an ACTIVITYGRAM and inactivity from reported television programme viewing in 332 girls (ages 9 - 12 yrs, grades 4 - 5). Body composition (WHO BMI percentiles and percentage body fat) was used as an indirect measure of validity for the PAQ. Test-retest reliability of the PAQ was assessed in a convenience sample of 14 girls. Results. Weak but significant associations were found between the body composition and PAQ-derived total energy expenditure (r=-0.18; p<0.05 for percentage body fat; r=-0.17; p<0.01 for WHO BMI percentiles) and inactivity (r=0.35; p<0.001 for percentage body fat; r=0.23; p<0.001 for WHO BMI percentiles). Positive associations were found between moderate and vigorous energy expenditure by PAQ and the same intensity activities by ACTIVITYGRAM (r=0.19; p<0.001 and r=0.26; p< 0.001, respectively). Further, the television viewing time reported by PAQ was significantly positively related to the number of programmes noted from the television programme list. Only total energy expended while partaking in structured school sports showed good test-retest reliability (r=0.80; p<0.05). Conclusions. Our results showed that the PAQ may provide some reasonable insights into levels of physical inactivity and activity in South African primary schoolgirls. However, additional studies are required using objective measures of physical activity, such as pedometry or accelerometry, to better understand the utility of the PAQ for children.

South African Journal of Sports Medicine Vol. 19 (5) 2007: pp. 117-124