Tiered school-family-clinic intervention for childhood obesity prevention in China: A nested cluster randomized...

Childhood obesity is a pressing global public health challenge requiring scalable prevention strategies. This study evaluated a tiered school-family-clinic intervention for obesity prevention among primary schoolchildren in China.

This cluster randomized controlled trial enrolled 1,627 third-grade students (intervention: n = 838; control: n = 789) from six primary schools in Ningbo, China. Intervention intensity was tailored to baseline weight status. In intervention schools, children without overweight or obesity received OptiChild, comprising health education and school weight-management policies. Children with overweight or obesity received SCIENT, adding teacher-led structured physical activity and individualized family dietary guidance from clinical nutritionists, supported by mobile health tools. Control schools maintained standard curricula. The primary outcome was change in body mass index (BMI). Secondary outcomes included BMI Z score, body fat distribution, blood pressure, and health behaviors.

After one academic year, BMI gain was attenuated in the intervention vs. control group (+0.02 vs. +0.24 kg/m²; mean difference [MD] -0.25; p = 0.006). Overweight/obesity prevalence declined from 24.8% to 18.9% in intervention schools vs. 23.6%-21.0% in controls (p = 0.015). OptiChild slowed BMI increase (+0.08 vs. +0.25 kg/m²; MD -0.19; p = 0.048) in children without baseline overweight and reduced incident overweight/obesity by 68% (1.1% vs. 3.5%; p = 0.007). SCIENT reduced BMI (-0.19 vs. +0.21 kg/m²; MD -0.38; p < 0.001). Both interventions improved health behaviors, with no adverse events reported.

A tiered school-family-clinic intervention effectively mitigated BMI gain and reduced obesity prevalence, with promising implications for broader public health adoption.

Major Science and Technology Projects for Health of Zhejiang Province.