[1] Univ N Carolina, Carolinas Simulat Ctr, Carolinas Med Ctr, Div Gastrointestinal & Minimally Invas Surg, Charlotte, NC 28203 USA
[2] New Hanover Reg Med Ctr, Dept Surg, South East Area, Hlth Educ Ctr, Wilmington, NC USA
[3] Tulane Univ, Dept Surg, Hlth Sci Ctr, New Orleans, LA 70118 USA
[4] UT SW Med Ctr, Dept Surg, Dallas, TX USA