Generation Healthy Kids: A Cluster-randomized Trial of a Multi-component, Multi-setting Intervention

The GHK intervention was developed according to the United Kingdom Medical Research Council's framework for developing and evaluating complex interventions. A pilot- and feasibility study was conducted during December 2022-April 2023, and the intervention was subsequently adapted and adjusted.

The GHK main trial is a two-school-year cluster-randomized school- and community trial designed to investigate the effect of the multi-setting, multi-component GHK intervention program on weight development, health and wellbeing in Danish children aged 6-11 years. The trial will include 24 schools in Denmark (12 intervention and 12 control).

The primary aim of the cluster-randomized trial is to investigate whether the GHK intervention program can promote healthy body composition as measured by fat mass (FM) in the intervention group compared with the control group. We hypothesize that the intervention will result in less FM gain in the intervention group compared with the control group over the two school-year study period.

Generation Healthy Kids is a cluster-randomized school and community trial in which 24 schools will be randomly allocated to intervention or control. Schools are evenly distributed in two areas of Denmark: DK-EAST (Capital Region of Denmark and Region Zealand) and DK-WEST (Region of Southern Denmark). The overall study objective is to investigate if a 2-school-year multi-setting, multi-component intervention focusing on healthy diets, physical activity, sleep and screen media habits in the school and local community can promote healthy weight and body composition in children who are in 1st and 2nd grade at inclusion (i.e., age 6-9 years at inclusion). We will also investigate the intervention's effects on dietary intake and nutritional status; food literacy; family- and school meal culture, physical literacy, activity levels, and fitness; sleep and screen media habits; growth; cardio metabolic health; cognitive and motor functions; school performance; and mental health and well-being. Furthermore, we will evaluate the context, implementation and working mechanisms of the intervention.

In continuation of the above, we will investigate if the intervention can reduce social inequality in the outcomes, as well as explore potential effect modifiers such as sex, ethnicity, implementation levels, genetics, epigenetics etc. We will also explore associations between sociodemographic characteristics, health behaviors and outcomes cross-sectionally and longitudinally and use these data to validate and compare relevant measurement tools.

The innovative aspects of the Generation Healthy Kids study are the combination of an intervention targeting several important risk factors for excessive weight gain (dietary habits, physical activity, sleep, and screen time) with community capacity building and a systems approach. The unique combination is closely monitored for effect as well as process. The integrated intervention program will be distinctive in combining already tested effective intervention strategies with intervention components developed using co-creation and a systems mapping and working in varying settings of the child's life. Systems thinking will furthermore be used to ensure that a health equity lens is employed to understand the relationship between obesity and health inequalities locally. To reach children and families with low socio-economic status, focus will be on developing interventions that make healthy choices easy by creating healthy environments around the children, both at school and during leisure time.

Eligibility Criteria:
Inclusion Criteria:

* All children attending 1st or 2nd grade in the recruited schools

Exclusion Criteria:

- No exclusion criteria will be applied. If parents, teachers or research staff judge that a child cannot participate in certain parts of the intervention or measurement schedule, e.g. due to severe allergies, chronic diseases or mental/physical disabilities, the child will be eligible to participate in the remaining parts of the study.