Fig. 3From: The impact of long-term school-based physical activity interventions on body mass index of primary school children – a meta-analysis of randomized controlled trialsThe funnel plot for the 18 studies. The horizontal axis is the coefficient of SMD for BMI change in intervention groups and control groups, and vertical axis (s.e.of: SMD) is the reciprocal of SMD for BMI change in intervention groups and control groups. Random effect was used for the analysisBack to article page