[1] Natl Heart Lung & Blood Inst Framingham Heart Stu, Framingham, MA USA
[2] Emory Univ, Sch Med, Div Gen Med, Atlanta, GA USA
[3] Boston Univ, Sch Med, Dept Cardiol Prevent Med & Neurol, Boston, MA 02118 USA
[4] Boston Univ, Dept Math, Boston, MA 02215 USA
[5] Boston Univ, Sch Publ Hlth, Dept Biostat, Boston, MA USA
[6] Beth Israel Deaconess Med Ctr, Div Cardiol & Clin Epidemiol, Boston, MA 02215 USA
[7] Natl Heart Lung & Blood Inst, Bethesda, MD USA