One parent or parent surrogate of each participating adolescent was asked to complete a self-administered questionnaire (SAQ) that contained informant questions about the adolescent’s mental health. The full SAQ was completed by 6,491 parents. These recruitment and consent procedures were approved by the Human Subjects Committees of both Harvard Medical School and the University of Michigan. Once the survey was completed, cases were weighted for variation in within-household probability of selection (in the household sub-sample) and for residual discrepancies between the sample and the US population on the basis of socio-demographic and geographic variables. These weighting procedures are discussed in more detail elsewhere.18, 20 Socio-demographic variables assessed in the NCS-A include age (in years), sex, race/ethnicity, parent education, urbanicity, and marital status of parents. A poverty index ratio, based on family size and the ratio of family income to the family’s poverty threshold level, (≤1.5 poor, ≤3, ≤6, and > 6) was also included.
