1. Department of Surgery; Kaiser Permanente; Los Angeles; California; USA
2. Department of Colorectal Surgery; University of Southern California; Los Angeles; California; USA
3. Research and Evaluation; Kaiser Permanente Southern California; Pasadena; California; USA
4. Department of Radiology; Kaiser Permanente; West Los Angeles; California; USA
5. Department of Surgery; Mayo Clinic; Phoenix; Arizona; USA