Attention deficit hyperactivity disorder (ADHD) is a frequent condition in school-age children and commonly presents in comorbidity with other psychiatric diseases. In Brazil, there are few studies concerning non-clinical samples.
Purpose: The present study aims to calculate the prevalence of this disorder and its comorbidities in a sample of school-age children.
Method: Cross-sectional analytic study was conducted on a non-clinical sample of children and adolescents registered in 2003 in the elementary school of the Federal University of Rio de Janeiro. A screening questionnaire was used and parents of those possible affected children were invited for a clinical structured interview.
Results: The prevalence of ADHD was 8.6%. Comorbidities were present in 58% of the cases and oppositional-defiant disorder was the most common, found in 38.5%.
Conclusions: The prevalence of ADHD and its comorbidities in this sample is similar to that observed in the literature.