1. Department of Medical Epidemiology and Biostatistics (E.I.), Karolinska Institutet, SE-171 77 Stockholm, Sweden
2. The Framingham Study (E.I., M.G.L., X.Y., T.J.W., E.J.B., R.S.V.), Boston University School of Medicine, Framingham, Massachusetts 01702-5803
3. Department of Mathematics and Statistics (M.G.L.), Boston University School of Medicine, Boston, Massachusetts 02215
4. Department of Biostatistics (X.Y.), Boston University School of Public Health, Boston, Massachusetts 02118
5. Massachusetts General Hospital and Harvard Medical School (T.J.W.), Massachusetts General Hospital, Boston, Massachusetts 02114
6. Department of Medicine (J.B.M.), Massachusetts General Hospital, Boston, Massachusetts 02114
7. Boston University, and Evans Memorial Department of Medicine and Whitaker Cardiovascular Institute (I.L., E.J.B., R.S.V.), Boston University School of Medicine, Boston, Massachusetts 02215
8. Division of Cardiovascular Medicine (J.F.K.), University of Massachusetts Medical School, Worcester, Massachusetts 01655