[1] Northwestern Univ, Dept Surg, Surg Outcomes & Qual Improvement Ctr, Feinberg Sch Med, 633 N St Clair St,20th Floor, Chicago, IL 60611 USA
[2] Thomas Jefferson Univ Hosp, Dept Surg, Philadelphia, PA 19107 USA
[3] Amer Coll Surg, Chicago, IL USA
[4] Northwestern Univ, Dept Med Social Sci, Chicago, IL 60611 USA
[5] Ann & Robert H Lurie Childrens Hosp, Div Pediat Surg, Chicago, IL USA
[6] Virginia Tech, Carilion Sch Med, Dept Surg, Roanoke, VA USA
[7] Indiana Univ Sch Med, Dept Surg, Indianapolis, IN 46202 USA
[8] Univ Wisconsin, Dept Surg, Sch Med & Publ Hlth, Madison, WI USA