Subjects were recruited at five US sites for studies of the genetics of AD, CD and OD: Yale University School of Medicine (n=3461), the University of Connecticut Health Center (n=3336), the University of Pennsylvania School of Medicine (n=669), the Medical University of South Carolina (n=594), and McLean Hospital, an affiliate of Harvard Medical School (n=211). The institutional review boards at each of the participating sites approved the study. Written informed consent was obtained from all participants. All subjects were interviewed by trained interviewers using the Semi-Structured Assessment for Drug Dependence and Alcoholism (SSADDA) to derive diagnoses for lifetime psychiatric and substance use disorders based on DSM-IV criteria (Pierucci-Lagha et al., 2007; Pierucci-Lagha et al., 2005). The inter-rater and test-retest reliabilities of the SSADDA for the lifetime diagnoses of AD, CD and OD based on DSM-IV were excellent (Pierucci-Lagha et al., 2005).
