1. Dr. Goldberg and Dr. Comstock are with the Department of Epidemiology, Johns Hopkins University School of Hygiene and Public Health, Baltimore, Md., where Dr. Goldberg is Assistant Professor and Dr. Comstock is Professor. Dr. Hornstra is Associate Director, Greater Kansas City Mental Health Foundation, Kansas City, Mo. Address reprint requests to Dr. Goldberg at Training Center for Public Health Research, Box 2067, Hagerstown. Md. 21740.