1. Division of Cardiology, University of Texas Southwestern Medical Center, Dallas (R.K.).
2. Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, CT (H.M.K.).
3. Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT (H.M.K.).
4. Department of Health Policy and Management, Yale School of Public Health, New Haven, CT (H.M.K.).