1. Stanford University School of Medicine, Stanford, California
2. Health Economics Resource Center, Department of Veterans Affairs, Palo Alto, California
3. Stanford-Surgery Policy Improvement Research and Education Center, Stanford, California
4. Stanford Center for Population Health Sciences, Stanford, California
5. Surgical Service, Palo Alto Veterans Affairs Health Care System, Palo Alto, California
6. Department of Surgery, Stanford University School of Medicine, Stanford, California