1. Kingston General Hospital; Department of Surgery; 76 Stuart Street Kingston ON Canada K7L 2V7
2. University of Toronto; Division of Trauma, Department of General Surgery; Toronto ON Canada
3. University of Illinois School of Public Health; Epidemiology/Biometry Division; 1603 West Taylor Room 956 Chicago Illinois USA 60612
4. Johns Hopkins University; 3400 N. Charles Street Baltimore Maryland USA 21218
5. Cleveland Clinic; Department of Colorectal Surgery; Cleveland Ohio USA 44106