Body mass Index of children and adolescent participants in a voucher program designed to incentivise participation in sport and physical activity: A cross-sectional study.

There has been limited population-level success in tackling overweight and obesity. The Active Kids program is a universal intervention that aims to increase participation in structured physical activity and sport among children and adolescents in New South Wales (NSW), Australia. This study examined the prevalence of overweight and obesity across subgroups and by social disadvantage in this large broadly representative sample. A cross-sectional study was conducted including all children (n = 671,375) who registered for an Active Kids Program voucher in 2018. The child's height and weight were obtained from an online registration form. Among children and adolescents who registered in the Active Kids Program, the prevalence of overweight and obesity was 17.2% and 7.6%, respectively. A large number of children and adolescents who lived in the most disadvantaged areas (n = 99,583; 14.8%) registered for the program. There was a clear socio-economic gradient for obesity prevalence across areas of increasing disadvantage, with children and adolescents living in the most disadvantaged area being 1.87 (95% CIs 1.82, 1.93) times more likely to be overweight or obese. The Active Kids program successfully reached a substantial proportion of children who are overweight and obese from socio-economically disadvantaged areas, providing financial support and opportunities for these children to participate in structured sport and physical activity. However, the program did not reach all children, and additional physical activity promotion strategies may be needed in a comprehensive approach. Nonetheless, these findings support government investment in reaching children who are overweight or obese with large-scale programs.