An epidemiological perspective of obsessive-compulsive disorder in children and adolescents.

Obsessive-compulsive disorder (OCD) is reviewed from an epidemiological perspective. OCD is defined according to the DSM-IV and ICD-10, with differences noted between these two classification systems. The epidemiological rubrics of quantity (prevalence), location (genetic methods and gender differences), cause (genetic etiology), and causal mechanisms (natural history and clinical course) are reviewed. The review concludes that more research is needed to further understand the epidemiology of OCD in children and adolescents, both from a Canadian and worldwide perspective.