1. From the Dartmouth Institute for Health Policy and Clinical Practice, Lebanon, NH (N.R., J.R.B., P.P.G.); Section of Vascular Surgery, Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH (B.D.S., J.L.C., P.P.G.); and Weill Cornell Medical College, Cornell University, New York, NY (A.S.).