Reliability and validity of the Sinhala version of the physical activity questionnaire for older children (PAQ-C)

Introduction In Sri Lanka, as non-communicable diseases rise, the significance of physical activity is increasingly recognised, particularly in children. The Physical Activity Questionnaire for Older Children (PAQ-C) is widely used and can be considered as one of the best available tools for assessing physical activity in children. However, a validated tool for Sinhala-speaking children in Sri Lanka has been lacking. This study aims to culturally adapt and validate the PAQ-C for Sinhala-speaking children and evaluate its psychometric properties. Methodology This cross-sectional study involved 301 schoolchildren (197 males and 104 females) aged 8–11 years, during which the PAQ-C was translated into Sinhala, and a pre-final version was developed. In terms of validity, content validity, that is, the degree to which the content of an instrument is an adequate reflection of the construct to be measured, was assessed using the content validity index. In terms of reliability, test-retest reliability was measured with the intraclass correlation coefficient (ICC). Results The Sinhala version of the PAQ-C demonstrated CVI at both item and scale levels is as one. The ICC was acceptable at 0.83. Conclusion The Sinhala version of the PAQ-C demonstrates good content validity and acceptable test–retest reliability, affirming its suitability as a cost-effective tool for assessing physical activity levels among Sinhala-speaking children in Sri Lanka and supporting informed interventions and public health strategies in the country.