Validity of the International Physical Activity Questionnaire (short form) in adults with asthma

BACKGROUND: The short form of the International Physical Activity Questionnaire (IPAQ) is widely used to assess PA and has already been used in adults with asthma; however, its validity has not been yet studied in this population. Therefore, the aim of this study was to verify the convergent and discriminative validity of the IPAQ short form in adults with asthma. METHODS: Fifty-three adults with asthma (36 females; 48±15 years; 29±6 kg/m²) wore the triaxial activity monitor Actigraph for eight days to objectively measure steps/day, time in light physical activity (PA), moderate-to-vigorous PA (MVPA), and sedentary behaviour. Participants filled out the IPAQ matching with the same week they wore the Actigraph, with measures of: time of MVPA and total PA/week; categorization of low, moderate or high PA level; time in seated position. RESULTS: IPAQ self-reported total time of PA/week was weakly correlated with steps/day. The IPAQ categorization correlated moderately with time in light, MVPA and steps/day. Self-reported time in seated position on weekdays was moderately correlated with objective percentage/day of time in sedentary behaviour in the same period. IPAQ categorization in PA levels was able to differentiate between low to moderate and low to high PA levels. CONCLUSIONS: These results cannot confidently infer the convergent validity of the IPAQ to quantify number of steps/day and time spent in PA of adults with asthma. However, this instrument may be useful to categorize patients into three levels of PA.