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

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.

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.

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.

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.