1. Departments of Medicine (D.C.B.) San Francisco, San Francisco, California 94107
2. Epidemiology and Biostatistics (D.C.B., D.M.B., L.P.), University of California, San Francisco, San Francisco, California 94107
3. Synarc and Institut National de la Santé de la Recherche Médicale Unit 403 (P.G.), Lyon, France
4. Department of Medicine (J.P.B.), College of Physicians and Surgeons, Columbia University, New York, New York 10027
5. University of Pittsburgh (S.L.G.), Pittsburgh, Pennsylvania 15213
6. Departments of Medicine and Epidemiology (K.E.E.), Minneapolis Veterans Affairs Medical Center and University of Minnesota, Minneapolis, Minnesota 55417
7. the Maine Center for Osteoporosis Research (C.J.R.), St. Joseph Hospital, Bangor, Maine 04401