Overweight prevention implemented by primary school teachers: a randomised controlled trial

To describe the effects of URMEL-ICE, a German school-based intervention for overweight prevention, on children's BMI and other measures of fat mass.

A cluster-randomised controlled design was used. The intervention which focused on physical activity, TV time and soft drink consumption was integrated into a second-grade curriculum and was implemented by classroom teachers themselves. It comprised 29 teaching lessons, 2 short exercise blocks per day and 6 family homework lessons. BMI was assessed as primary outcome measure, waist circumference and skinfold thickness as secondary outcomes. Data of 945 children were analysed.

Multivariate analyses adjusted for baseline values showed no statistically significant effect of the intervention on BMI, but on waist circumference (-0.85; 95% confidence interval (95% CI) -1.59 to -0.12) and subscapular skinfold thickness (-0.64; 95% CI -1.25 to -0.02). After additional adjustment for individual time lag between baseline and follow-up, these effects were reduced to -0.60 (95% CI -1.25 to 0.05) and -0.61 (95% CI -1.26 to 0.04) and lost their statistical significance.

This study contributes to the field of randomised school-based studies on overweight prevention and shows that within a 1-year, integrated intervention no effect on BMI, but a tendency towards effects on fat mass can be achieved.