1. From the Division of Cardiovascular Medicine, Duke University Medical Center (S.J.D., J.E.T., C.M.O.) and Duke Clinical Research Institute (S.J.D., D.M.V., J.E.T., C.M.O.), Durham, NC; Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis (D.M.V.); Section of Cardiology, North Florida/South Georgia Veterans Affairs, Gainesville, FL (C.M.S.); and Department of Internal Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH (G.D.Y.).