Epidemiology of childhood conduct problems in Brazil: systematic review and meta-analysis.

Purpose: This study aimed to review evidence on the prevalence of and risk factors for conduct problems in Brazil.

Methods: We searched electronic databases and contacted Brazilian researchers up to 05/2012. Studies were included in the review if they reported the prevalence of or risk factors for conduct problems, conduct disorder, or oppositional defiant disorder for 100 + Brazilian children aged ≤18 years, systematically sampled in schools or the community. Prevalence rates and sex differences were meta-analysed. Risk factor studies were reviewed one by one.

Results: The average prevalence of conduct problems in screening questionnaires was 20.8%, and the average prevalence of conduct disorder/oppositional defiant disorder was 4.1%. There was systematic variation in the results of screening studies according to methodology: recruitment location, informants, instruments, impairment criterion for case definition, and response rates. Risk factors previously identified in high-income countries were mainly replicated in Brazil, including comorbid mental health problems, educational failure, low religiosity, harsh physical punishment and abuse, parental mental health problems, single parent family, and low socioeconomic status. However, boys did not always have higher risk for conduct problems than girls.

Conclusions: Studies using screening questionnaires suggest that Brazilian children have higher rates of conduct problems than children in other countries, but diagnostic studies do not show this difference. Risk factors in Brazil were similar to those in high-income countries, apart from child sex. Future research should investigate developmental patterns of antisocial behaviour, employ a variety of research designs to identify causal risk mechanisms, and examine a broader range of risk factors.