The epidemiology of childhood psychiatric disorders: prevalence findings from recent studies.

While sharing a new emphasis upon identifying discrete psychiatric disorders in children and adolescents, epidemiological field studies conducted during the past decade have used diverse methods of case ascertainment and definition. Half used the multimethod-multistage approach to ascertain cases. Severity rating scales and measures of pervasiveness, parent-child concordance, and global functional impairment were employed to enhance the specificity of case definition. The majority of overall prevalence estimates of moderate to severe disorder range from 14 to 20%. Those investigations that use multiple methods to define caseness show greatest promise in identifying true cases in community samples.