Process evaluation of a school-based overweight and obesity screening strategy in adolescents.

The PRALIMAP (PRomotion de l'ALIMentation et de l'Activité Physique) trial highlights the effectiveness of implementing a screening strategy in high schools to prevent overweight/obesity among adolescents. The strategy comprises three steps: i) body measurements to detect overweight/obese adolescents, ii) a medical interview with each adolescent identified to discuss the findings, and iii) an adapted care management consisting of seven group educational sessions. A process evaluation was conducted in the PRALIMAP trial to assess the effective implementation of the screening strategy activities, and the participation of adolescents and school professionals in them, from a qualitative and a quantitative point of view. The present paper describes the process and the implementation of the screening strategy as performed in the PRALIMAP trial, and discusses the feasibility of such an intervention in high school settings. The ability of nurses to explain the screening results improved with the addition of specialist support. The ability of adolescents to take part in the screening strategy improved when the adapted care management was conducted inside schools and could be increased even further if the waiting time between the three steps could be minimised.