1. Department of Surgery, Massachusetts General Hospital, Boston, MA (T.F.X.O.).
2. Division of Vascular and Endovascular Surgery (T.F.X.O., M.L.S.), Beth Israel Deaconess Medical Center, Boston, MA.
3. Department of Health Care Policy, Harvard Medical School, Boston, MA (B.E.L.).
4. Division of General Medicine and Primary Care (B.E.L.), Beth Israel Deaconess Medical Center, Boston, MA.