Implementation evaluation: Study protocol
The evidence-based Dutch Obesity Intervention in Teenagers (DOiT) programme is a school-based obesity prevention programme for 12- to 14-year-olds attending the first two years of prevocational education. This paper describes the study protocol applied to evaluate (a) the nationwide dissemination process of DOiT throughout the Netherlands, and (b) the relationship between degree of implementation and effectiveness during nationwide dissemination of the programme in the Netherlands.
In order to explore the facilitating factors and barriers for dissemination of DOiT, we monitored the process of adoption, implementation and continuation of the DOiT programme among 20 prevocational schools in the Netherlands. The study was an observational study using qualitative (i.e. semi-structured interviews) and quantitative methods (i.e. questionnaires and logbooks). Eight process indicators were assessed: recruitment, context, reach, dosage, fidelity, satisfaction, effectiveness and continuation. All teachers, adolescents and parents involved in the implementation of the programme were invited to participate in the study. As part of the process evaluation, a cluster-controlled trial with ten control schools was conducted to evaluate the effectiveness of the programme on adolescents’ adiposity and energy balance-related behaviours and its association with quality of implementation.
The identified impeding and facilitating factors will contribute to an adjusted strategy promoting adoption, implementation and continuation of the DOiT programme to ensure optimal use and, thereby, prevention of obesity in Dutch adolescents.