Major depression and dysthymia in children and adolescents: Discriminant validity and differential consequences in a community sample

Objectives: To evaluate evidence, in a community sample, for discriminant v alidity between major depression (MDD) and dysthymia (Dy) in children and a dolescents and to examine differential consequences of the 2 disorders for functioning. Method: The National Institute of Mental Health (NIMH) Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) study consists of probability samples of youths. Data for this study are derived from interviews with 1,285 complete parent-youth pairs aged 9 to 17 years from 4 geographic areas in the United States. Youths with MDD were contrast ed with those with Dy and those with both (MDD-Dy) on the NIMH Diagnostic i nterview Schedule for Children, Non-Clinician Children's Global Assessment Scale, Columbia Impairment Scale, and the Service Utilization and Risk Fact ors Module. Results: Groups with MDD, Dy, or MDD-Dy did not differ on socio demographic, clinical, or family and life event variables. Youths with comb ined MDD-Dy were significantly less competent and more impaired than youths with either disorder alone. Conclusions: The findings do not provide suppo rt for the differentiation of MDD and Dy but strongly suggest the importanc e of addressing the needs of youths who meet criteria for both MDD and Dy b ecause this combination is likely to be both serious and disruptive of norm al developmental processes.