1. Section of Colon and Rectal Surgery, Division of General Surgery, Stanford University School of Medicine, Stanford, California, USA
2. Stanford-Surgery Policy Improvement Research & Education Center, Stanford University School of Medicine, Stanford, California, USA
3. Department of Surgery, Wellington Regional Hospital, Wellington, New Zealand
4. Department of Surgery and Anaesthesia (Wellington), University of Otago, New Zealand
5. Department of Surgery, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
6. Section of Colon and Rectal Surgery, Division of General Surgery, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
7. VA Greater Los Angeles Healthcare System, Los Angeles, California, USA