Abstract
Effectiveness of school-based interventions to prevent or control overweight and obesity among school children was reviewed for a 11-year period (January 2001 to December 2011). All English systematic reviews, meta-analyses, reviews of reviews, policy briefs and reports targeting children and adolescents which included interventional studies with a control group and aimed to prevent or control overweight and/or obesity in a school setting were searched. Four systematic reviews and four meta-analyses met the eligibility criteria and were included in the review. Results of the review indicated that implementation of multi-component interventions did not necessarily improve the anthropometric outcomes. Although intervention duration is a crucial determinant of effectiveness, studies to assess the length of time required are lacking. Due to existing differences between girls and boys in responding to the elements of the programs in tailoring of school-based interventions, the differences should be taken into consideration. While nontargeted interventions may have an impact on a large population, intervention specifically aiming at children will be more effective for at-risk ones. Intervention programs for children were required to report any unwanted psychological or physical adverse effects originating from the intervention. Body mass index was the most popular indicator used for evaluating the childhood obesity prevention or treatment trials; nonetheless, relying on it as the only indicator for adiposity outcomes could be misleading. Few studies mentioned the psychological theories of behavior change they applied. Recommendations for further studies on school-based interventions to prevent or control overweight/obesity are made at the end of this review.