Effectiveness and cost-effectiveness of a 1-year dietary and physical activity intervention of childhood obesity—study protocol for a randomized controlled clinical trial

Abstract Background We investigate and try to find out the optimal duration and intensity for the treatment and content useful for clinical work. The aim of our study is to evaluate the effects of lifestyle intervention on the management of childhood overweight and to explore the factors that contribute to the outcome, as well as the costs for the health care system. The hypotheses of the study are that lifestyle intervention is efficient in reducing BMI-SDS and thus effective in preventing overweight from progressing to obesity, and it is also cost-effective. Methods and analyses We aim to recruit 80 children and they randomize either to an intervention group or a control group with standard care. The intervention group receives intensive, family-based diet, and physical activity counseling, delivered by a multidisciplinary team of a pediatrician, a nurse, and a clinical nutritionist. The control group does not receive any lifestyle intervention during the study. The inclusion criteria are age of 6–12 years, weight-for-height ≥ + 40% or ≥ + 30%, and increasing curve. All participants fill out the study questionnaires and plasma samples are taken at baseline and at 12 months. Outcome variables will be compared between intervention and control groups. Discussion If the effects of this lifestyle intervention are positive and it is also cost-effective, the implication of our study will be of great importance to the treatment of childhood obesity and to improve the health care system. Trial registration ClinicalTrials.gov NCT06126679. Registered on 25 October 2028 in Finland. ORCID: 0009-0009-6659-5290.