Factors associated with the effectiveness of interventions to prevent obesity in children: a synthesis of evidence from 204 randomised trials
Authors:
Open Access
- 1 January 2025
- journal article
- Published by BMJ in BMJ Public Health
- Vol. 3 (1) , e001707
Abstract
Introduction: We aim to identify effective characteristics of behavioural change (physical activity and diet) interventions that prevent obesity in children aged 5 to 18 years. Methods: We re-analysed data from two Cochrane systematic reviews published in 2024 using a Bayesian multi-level meta-regression analysis with intervention and trial characteristics coded according to an analytic framework co-developed with stakeholders. Results: We included 204 trials (255 intervention arms) reporting data on body mass index (BMI), either unstandardised or measured as a z-score (zBMI) or percentile. Interventions were effective on average (MD in zBMI −0.037, 95% credible interval −0.053 to −0.022). The greatest effects were associated with medium-term follow-up (nine to <15 months) and older children (12 to 18 years). We found evidence of small beneficial effects for interventions targeting physical activity alone compared with diet alone (difference in MDs −0.227,–0.362 to −0.090) and small unfavourable effects for interventions that involved a change to the structural environment (typically the school food environment) (difference in MDs 0.05, 0.017 to 0.085). Accounting for interactions between covariates, the most effective combination of intervention characteristics was to intervene in the school setting, with an individualised element to delivery, targeting physical activity, using multiple strategies of short duration and high intensity and involving modification of behaviour through participation in activities. Conclusions: The most effective characteristic to include in a behavioural change intervention to prevent obesity in children aged 5–18 years was targeting of physical activity. This should not be interpreted as evidence that attempts to modify diet are not beneficial. Being physically active and consuming a healthy diet during childhood offer many important benefits beyond contributing to healthy weight and growth. Our findings suggest that interventions to prevent obesity in children should consider increasing their focus on the promotion of physical activity and consider other effective characteristics we identify here.Keywords
All Related Versions
Funding Information
- National Institute for Health Research Applied Research Collaboration West (NIHR200181)
- NIHR Bristol Evidence Synthesis Group (NIHR153861)
- National Institute for Health and Care Research (NIHR) Senior Investigator Award (NIHR203807)
- Public Health Research Programme (NIHR131572)
- Engineering and Physical Sciences Council (EP/Y007905/1)
This publication has 21 references indexed in Scilit:
- Do the effects of interventions aimed at the prevention of childhood obesity reduce inequities? A re-analysis of randomized trial data from two Cochrane reviewseClinicalMedicine, 2025
- A Complex Meta‐Regression Model to Identify Effective Features of Interventions From Multi‐Arm, Multi‐Follow‐Up TrialsStatistics in Medicine, 2024
- Mapping between measurement scales in meta‐analysis, with application to measures of body mass index in childrenResearch Synthesis Methods, 2024
- A novel analytic framework to investigate differential effects of interventions to prevent obesity in children and young peoplemedRxiv, 2024
- Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adultsThe Lancet, 2024
- Estimating the effects of preventive and weight-management interventions on the prevalence of childhood obesity in England: a modelling studyThe Lancet Public Health, 2023
- Child and adolescent obesityNature Reviews Disease Primers, 2023
- School environments and obesity: a systematic review of interventions and policies among school-age students in Latin America and the CaribbeanInternational Journal of Obesity, 2022
- Bayesian models for aggregate and individual patient data component network meta‐analysisStatistics in Medicine, 2022
- Targeting childhood obesity through primary schools: reviewing alignment amongst English policies for physical activity and healthy eatingChild and Adolescent Obesity, 2020