PS03 Systematic Review and Meta-Analysis of School-Based Interventions to Reduce Body Mass Index

Abstract

Background Childhood obesity predisposes to adult obesity and increases the risk of many diseases. Schools provide a vehicle to deliver public health interventions to all children.MethodsMedline and Embase were used to undertake a systematic review of published studies of school-based interventions aimed at reducing the body mass index (BMI) of children < 18 years. Preferred reporting items for systematic reviews and meta-analyses guidelines were followed, and eligible studies subjected to a random effects meta-analysis.ResultsBetween 1991 and 2010, 43 published studies provided 60 measurements of effect. The pooled effect was a 0.17 (95 CI: 0.08, 0.26, P< 0.001) reduction in BMI. Heterogeneity was high (I2 93.4) but there was no significant small study bias (Egger's test, P 0.422) nor significant variation by length of follow-up. The intervention comprised physical activity only in 11 (26) studies, education only in three (7), and combinations of these and improved nutrition in the remaining 29 (67). On stratified analysis, physical activity used in isolation (-0.13, 95 CI:-0.22,-0.04, P 0.001) or combined with improved nutrition (-0.17, 95 CI:-0.29,-0.06, P< 0.001) was associated with significant improvements in BMI. Interventions targeted at overweight/obese children reduced their BMI by 0.35 (95 CI: 0.12, 0.58, P 0.003). Those delivered to all children reduced it by 0.16 (95 CI: 0.06, 0.25, P 0.002).ConclusionsThere is growing evidence that school-based interventions that contain a physical activity component may be effective in helping to reduce BMI in children. © 2012 The Author.