Does the intervention of the school-based health promotion programme 'Join the Healthy Boat' have equal or differential effects on weight status and health-related behaviours in children from a high or low socio-economic background? – A randomised controlled trial - Kobel, Susanne; Wartha, Olivia; Steinacker, Jürgen M.; Dreyhaupt, Jens (BMC Public Health, 2024)