1. Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University and the New York State Psychiatric Institute, and Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York (M.O.)
2. United States Census Bureau, Mortality Research Group, Suitland, Maryland (C.M.C.)
3. Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University and the New York State Psychiatric Institute, New York, New York (M.M.W.)
4. Division of Epidemiology, Services and Prevention Research, National Institute on Drug Abuse, Rockville, Maryland (C.B.).