Weight-related child behavioral interventions in Brazil: a systematic review.

Context: Between 1974 and 1997, the prevalence of overweight increased 300% among Brazilian children and adolescents. A systematic review was conducted between January 2010 and December 2011 of obesity-related interventions targeting Brazilian children and adolescents.

Evidence Acquisition: Manuscripts from 1965 to December 2010 were evaluated based on inclusion criteria including evaluating obesity-related outcomes and at least 50% of participants living in Brazil. Methods were adapted from the CDC's Community Guide. Evidence was based on the number of available studies, study design, execution, quality, and effect size.

Evidence Synthesis: Sixteen articles were abstracted; five met final inclusion criteria. All intervention samples (range n=14-78; mean n=40.6) included overweight or obese children aged 8-17 years. The intervention duration range was 3-6 months, and dose frequency ranged from two to five times per week. Three of the five interventions included healthy eating and physical activity; two included only physical activity. Two interventions studies were rated as having greatest design suitability. Only one intervention had the greatest design suitability and a large effect size.

Conclusions: Intervention approaches that combined physical activity and healthy eating had the strongest effects. However, small sample bias, 95% CIs of primary effects, and poor-to-moderate quality of research designs and implementation suggest the combined evidence is best rated as Insufficient. This prohibits the recommendation of specific strategies or settings. Findings suggest that more well-designed evidence-based childhood obesity interventions in Brazil are needed and that promising, but yet unproven, interventions should be evaluated rigorously.