1. From the Division of Pharmacoepidemiology and Pharmacoeconomics (D.H.S.), Division of Rheumatology, Immunology, and Allergy (D.H.S., E.W.K., L.A.M.), and Division of Preventive Medicine, Channing Laboratory (J.E.M., M.J.S., G.C.C.); Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Mass; Department of Epidemiology (E.B.R., M.J.S., G.C.C.), Harvard School of Public Health, Boston, Mass; and Merck Research Laboratories (C.C.C.), West Point, Pa.