The International Physical Activity Questionnaire (IPAQ) was originally developed to provide a self-report measure that can be used to obtain internationally comparable data on habitual physical activity. The objective of this study was to analyze the reproducibility and validity of IPAQ short form in a representative sample of adolescents. A total of 161 adolescents (92 girls and 69 boys) with ages between 12 and 18 years were included in the study. For the assessment of reproducibility, Spearman correlation coefficients and Bland-Altman plots were computed between administrations of the questionnaire at baseline, and after two weeks. Validity was determined by comparing questionnaire against a 24-hour recall instrument of the daily activities. Spearman correlation coefficients and proportion of agreement (Kappa values) were calculated, based on categorization of the distributions of the physical activity variables into quartiles. Results showed correlation coefficients ranging from 0.49 to 0.70 in girls and from 0.56 to 0.83 in boys, all statistically significant. Although these data are comparable to most other self-report reproducibility studies, Bland-Altman plots demonstrated limited concordance capacity between test-retest of the questionnaire. In terms of validity, the time spent in each activity reported in the IPAQ was modestly correlated with the 24-hour recall data (range 0.09-0.51). However, when the time spent in moderate and intense activities were reported, the validity indicators increased considerably, and the values observed were higher for older boys. In conclusion, these data provide evidence that, in adolescents of both genders and older than 14 years, the IPAQ have acceptable measurement properties for monitoring levels of habitual physical activity. Among younger adolescents (< 14 years old), findings indicate that the use of the IPAQ short form presents some limitations.
Measurement; Accuracy; Reliability; Validation; IPAQ
