Evaluation of an innovative family-centred care and prevention intervention for children with overweight and obesity: a mixed-methods study protocol of the randomised controlled fruehstArt study in Germany.

introductionChildhood overweight and obesity pose a growing public health problem with increasing prevalence both in Europe and globally. Reasons can be found in behavioural factors such as a sedentary lifestyle, eating habits or low exercise levels and to a lesser extent in a genetic predisposition or a metabolic disorder. Preventing children with obesity and overweight to grow into obese teenagers is therefore of high importance. However, there are currently no established care and prevention programmes in Germany for the early reduction of overweight and prevention of obesity in children aged 3-6 years. fruehstArt aims to close this gap with a cross-sector outreach and family-centred personal counselling approach, where parents receive support from paediatricians and trained coaches who conduct consultations in the home of the family. The main research question is whether the fruehstArt programme reduces overweight and obesity in children aged 3-6 years within 12 months, as measured by the body mass index-standard deviation score (BMI-SDS). METHODS AND ANALYSIS: fruehstArt has been developed as a new form of care, which includes a family intervention with motivational interviews provided by paediatricians and individual home-based counselling provided by a trained coach on eating behaviour, exercising, sleeping behaviour and age-appropriate use of electronic devices. fruehstArt will be accompanied by an efficacy study (summative evaluation of change in BMI-SDS). In addition to German, the project is also offered in Turkish in order to reach families with a migration background and language barriers. 812 children with overweight or obesity and their families in the region North Rhine will be included and observed over 12 months. Recruitment of children occurred from December 2023 to April 2025 with the final visits scheduled for April 2026. The study is conducted as a randomised controlled trial with a social-ecological intervention approach, considering children in their living environment and conditions. Moreover, a formative evaluation at the process level, and the system level will be carried out and complemented by a health economic analysis. Those are carried out to provide information about the intervention's success and relevant costs. Thus, fruehstArt is realised in the form of an effectiveness-implementation hybrid design that combines the analysis of effectiveness with an evaluation of the implementation process. ETHICS AND DISSEMINATION: The study received ethics approval in a coordinated procedure from the ethics committee of the Medical Faculty University hospital of Cologne and the ethics committee of the North Rhine Medical Association. For all collected data, the relevant national and European data protection regulations will be considered. All personal data (contact details) will be removed for the data analysis in order to ensure pseudonymisation. Dissemination strategies include reports and quality workshops for organisations, peer-reviewed publications and the presentation of results at conferences. DISCUSSION: The aim of the unique form of care fruehstArt is to improve the care of preschool children with overweight or obesity through innovative home-based counselling, cross-sectoral service integration and to address the cultural needs of Turkish families. TRIAL REGISTRATION NUMBER: DRKS00030749 (29-09-2023).