| Affiliation: | 1. Division of Cardiovascular Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pa;2. Division of General Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, Pa;3. Division of Cardiovascular Surgery, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada;1. Division of Vascular Surgery, Department of Surgery, University of Washington School of Medicine, Seattle, Wash;2. Division of Vascular Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, Ind;3. William M. Tierney Center for Health Services Research, Regenstrief Institute, Indianapolis, Ind |
