Development and psychometric properties of the Y-PASS questionnaire to assess correlates of lunchtime and after-school physical activity in children

BACKGROUND To frame interventions, it is useful to understand context- and time-specific correlates of children's physical activity. To do this, we need accurate assessment of these correlates. There are currently no measures that assess correlates at all levels of the social ecological model, contain items that are specifically worded for the lunchtime and/or after-school time periods, and assess correlates that have been conceptualised and defined by children. The aim of this study was to develop and evaluate the psychometric properties of the lunchtime and after-school Youth Physical Activity Survey for Specific Settings (Y-PASS) questionnaires. METHODS The Y-PASS questionnaire was administered to 264 South Australian children (146 boys, 118 girls; mean age = 11.7 ± 0.93 years). Factorial structure and internal consistency of the intrapersonal, sociocultural and physical environmental/policy lunchtime and after-school subscales were examined through an exploratory factor analysis. The test-retest reliability of the Y-PASS subscales was assessed over a one-week period on a subsample of children (lunchtime Y-PASS: n = 12 boys, 12 girls, mean age of 11.6 ± 0.8 years; after-school Y-PASS: n = 9 boys, 13 girls; mean age = 11.4 ± 0.9 years). RESULTS For the lunchtime Y-PASS, three factors were identified under each of the intrapersonal, sociocultural and physical environmental/policy subscales. For the after-school Y-PASS, six factors were identified in the intrapersonal subscale, four factors in the sociocultural subscale and seven factors in the physical environmental/policy subscale. Following item reduction, all subscales demonstrated acceptable internal consistency (Cronbach alpha = 0.78-0.85), except for the lunchtime sociocultural subscale (Cronbach alpha = 0.55). The factors and items demonstrated fair to very high test-retest reliability (ICC = 0.26-0.93). CONCLUSION The preliminary reliability and factorial structure evidence suggests the Y-PASS correlate questionnaires are robust tools for measuring correlates of context-specific physical activity in children. The multi-dimensional factor structure provides justification for exploring physical activity correlates from a social ecological perspective and demonstrates the importance of developing items that are context specific. Further development and refinement of the Y-PASS questionnaires is recommended, including a confirmatory factor analysis and exploring the inclusion of additional items.