Written parent informed consent and adolescent assent were obtained before surveying either the parent or adolescent. Each respondent was given $50 for participation. 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 within-household probability of selection (household sample) and deviation from Census population socio-demographic/geographic distributions, making each sample nationally representative on the socio-demographic/geographic variables. The samples were then merged with sums of weights proportional to relative sample sizes adjusted for design effects in estimating disorder prevalence. These procedures are detailed elsewhere (Kessler et al., 2009a; Kessler et al., 2009b).
