1. Health Economics Resource Center, VA Palo Alto Health Care System , Menlo Park, CA 94025 , United States
2. Stanford Surgery Policy Improvement and Education Center, Department of Surgery, Stanford University School of Medicine , Palo Alto, CA 94304 , United States
3. Department of Economics, University of California , Santa Cruz, Santa Cruz, CA 95064 , United States
4. Center for Innovation to Implementation, Palo Alto Veterans Affairs Health Care System , Menlo Park, CA 94025 , United States
5. Department of Emergency Medicine, University of California , San Franciso, CA 94143, United States
6. Department of Emergency Medicine (Affiliated), Stanford University School of Medicine , Stanford, CA 94305 , United States