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National comorbidity survey replication adolescent supplement (NCS-A): II. overview and design.(Survey)

The national comorbidity survey that seeks to determine the prevalence and correlates of mental disorders among U.S. adolescents is based on a dual-frame design that includes 904 adolescents from a previous household survey and 9,244 adolescent students from a sample of 320 schools. Replacement schools for those that refuse to participate do not produce bias.