Our knowledge of the prevalence and demographic and clinical characteristics of obsessive-compulsive disorder (OCD) has, until recently, been based almost exclusively on patient samples. The epidemiology of OCD was first described in a large United States household sample from the Epidemiologic Catchment Area (ECA) study. Since these original observations, the rates of OCD in household populations determined from diagnostic procedures similar to those used in the United States have been published from different parts of the world. Detailed comparisons of rates, sex ratios, age at onset, and demographic and clinical characteristics of OCD in these samples are now available.
This article reports on the cross-national epidemiology of OCD from seven international epidemiologic surveys, including the United States ECA study. Each survey used the Diagnostic Interview Schedule (DIS), a highly structured interview, developed for use in epidemiologic surveys, that yields Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM-III) psychiatric diagnoses. All investigators provided the data from their study to be pooled at Columbia University, and the prevalence rates were standardized to the age and sex distribution of the five-site ECA household population so that more precise estimates and comparisons could be made.