Carolyn C. Cannuscio, Camara Jones, Ichiro Kawachi, and Lisa Berkman are with the Department of Health and Social Behavior, Harvard School of Public Health, Boston, Mass. Carolyn C. Cannuscio is also with the Epidemiology Department, Merck Research Laboratories, Blue Bell, Pa. Camara Jones, Graham A. Colditz, and Eric Rimm are with the Department of Epidemiology, Harvard School of Public Health, Boston, Mass. Camara Jones is also with the Centers for Disease Control and Prevention, Atlanta, Ga. Graham A....