[1] Columbia Univ, Med Ctr, Dept Surg, Sect Thorac Surg, New York, NY USA
[2] Northwestern Univ, Dept Prevent Med, Chicago, IL 60611 USA
[3] Northwestern Univ, Feinberg Sch Med, Dept Surg, Chicago, IL 60611 USA
[4] Northwestern Univ, Dept Surg, Div Thorac Surg, Feinberg Sch Med, Chicago, IL 60611 USA
[5] Northwestern Univ, Ctr Healthcare Studies, Inst Publ Hlth & Med, Feinberg Sch Med, Chicago, IL 60611 USA
[6] Univ Wisconsin, Dept Surg, Div Cardiothorac Surg, Sch Med & Publ Hlth, Madison, WI USA