The sample for the current study was drawn from the National Epidemiological Survey of Alcohol and Related Conditions (NESARC) waves 1 and 2. The design and sample characteristics of NESARC have been previously described.19;37 Briefly, the NESARC is a survey of a nationally representative sample of the population in the United States, including residents of Hawaii and Alaska, conducted by the National Institute on Alcohol Abuse and Alcoholism (NIAAA). The interviews were conducted face-to-face with participants. To assure accurate estimates among racial and ethnic minority populations and among younger adults, the NESARC protocol included the oversampling of Blacks, Hispanics and young adults, ages 18 to 24 years. The NESARC sample was weighted to adjust for the unequal probabilities of selection and to provide nationally representative estimates.
