The NLAES (1991–92) and NESARC (2001–02) surveys focused on alcohol and drug use, DSM-IV substance use disorders and associated impairment in samples representative of the adult, non-institutionalized, civilian population of the United States. There were many methodological similarities between the two surveys, including the sampling universe and instrumentation used to assess alcohol dependence and related risk factors, such as family history of alcohol problems, major depression, and other disorders. Blacks were oversampled in both surveys and Hispanics were oversampled in the NESARC. Face-to-face interviews were administered by experienced lay interviewers from the U.S. Census Bureau. Respondents were informed about measures taken to ensure the confidentiality of the information they provided, and informed consent was obtained from all subjects. Ethical review and approval of all procedures was conducted by the U.S. Census Bureau and U.S. Office of Management and Budget; all subjects provided informed consent. The final NESARC sample consisted of 43,093 persons; overall raw response rate was 81%. The final NLAES sample consisted of 42,862 persons with a response rate of 90%. The analytical samples excluded those with missing height
