1. NHLBI's and Boston University's Framingham Heart Study; Framingham MA USA
2. Department of General and Interventional Cardiology; University Heart Center Hamburg Eppendorf; Hamburg Germany
3. Department of Cardiology; University Medical Center Groningen, University of Groningen; Groningen The Netherlands
4. Department of Biostatistics; Boston University School of Public Health; Boston MA USA
5. Center for Population Studies, Division of Intramural Research; National Heart, Lung, and Blood Institute, National Institutes of Health; Bethesda MD USA
6. Section of Cardiovascular Medicine; Boston University School of Medicine; Boston MA USA
7. Cardiology Division, Department of Medicine; University of Massachusetts Medical School; Worcester MA USA
8. Cardiovascular Research Center and Cardiac Arrhythmia Service; Massachusetts General Hospital; Boston MA USA
9. Cardiology Division; Massachusetts General Hospital; Boston MA USA
10. Evans Memorial Medicine Department; Boston University School of Medicine's Whitaker Cardiovascular Institute; Boston MA USA
11. Section of Preventive Medicine; Boston University School of Medicine; Boston MA USA
12. Departmeny of Epidemiology; Boston University School of Public Health; Boston MA USA