[1] Stanford Univ, Sch Med, Div Vasc Surg, 780 Welch Rd,Ste CJ350,MC 5639, Palo Alto, CA 94304 USA
[2] Surg Serv Line, Vet Affairs Palo Alto Healthcare Syst, Palo Alto, CA USA
[3] Stanford Univ, Sch Med, Stanford Surg Policy Improvement Res & Educ Ctr, Palo Alto, CA 94304 USA
[4] Ctr Hlth Equ Res & Promot, Vet Affairs Pittsburgh Healthcare Syst, Pittsburgh, PA USA
[5] Univ Pittsburgh, Dept Surg, Pittsburgh, PA USA
[6] Perioperat & Surg Care Serv, Atlanta Vet Affairs Healthcare Syst, Decatur, GA USA
[7] Emory Univ, Sch Med, Dept Surg, Atlanta, GA USA
[8] Morehouse Sch Med, Dept Surg, Atlanta, GA USA
[9] Univ Pittsburgh, Grad Sch Publ Hlth, Dept Biostat, Pittsburgh, PA USA
[10] Geriatr Res Educ & Clin Ctr, Vet Affairs Pittsburgh Healthcare Syst, Pittsburgh, PA USA
[11] Univ Pittsburgh, Med Ctr, Wolff Ctr, Pittsburgh, PA USA