Introduction: Childhood obesity disproportionately affects priority populations such as racial and ethnic minority groups and populations experiencing lower socioeconomic position1-3.
Objective: To identify the characteristics of the populations involved in interventions to prevent early childhood obesity, and understand whether and how priority populations have been targeted and reached in these interventions.
Methods: Systematic searches of medical databases and trial registries were conducted to identify all planned, ongoing and completed randomised controlled trials (RCTs) evaluating parent-focussed, behavioural interventions for childhood obesity prevention, starting within the first year of life4. Results were narratively summarised and tabulated based on trial-level data and participant characteristics.
Results: Fifty-one eligible RCTs were identified: 38 completed and 13 ongoing. Forty-six RCTs were conducted in high-income countries and five in upper middle-income countries. Participant recruitment or intervention was performed in metropolitan areas (36%), a combination of rural and urban areas (30%), urban (24%) and rural areas (9%). Priority populations were targeted in 28 RCTs. Among these, 5 of 19 completed RCTs did not reach their target population. The priority populations targeted were mothers with overweight/obesity, low health literacy, low socio-economic position as well as immigrants, people from specific ethnic/racial backgrounds and at risk of household food insecurity. Strategies to increase reach included delivering the intervention in additional languages (15 RCTs) and involving priority groups and stakeholders to design culturally appropriate resources (8 RCTs).
Conclusions: Few trials targeted priority populations and even the ones that did were not able to reach them. To achieve health equity and reach populations at greater risk of developing obesity, targeted recruitment strategies as well as culturally and linguistically tailored interventions are required.