1. Division of Cardiology, Hospital of the University of Pennsylvania, Philadelphia
2. Penn Cardiovascular Outcomes, Quality, and Evaluative Research Center, University of Pennsylvania, Philadelphia
3. Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia
4. Corporal Michael J. Crescenz VA Medical Center, Philadelphia, Pennsylvania
5. Duke Clinical Research Institute, Durham, North Carolina
6. Cardiovascular Research Foundation, New York, New York
7. St Francis Hospital, Roslyn, New York
8. Division of Cardiology, University of Michigan, Ann Arbor
9. Lahey Hospital and Medical Center, Burlington, Massachusetts
10. Division of Cardiac Surgery, Hospital of the University of Pennsylvania, Philadelphia