1. David Geffen School of Medicine, Department of Surgery, University of California, Los Angeles, Los Angeles
2. Veterans Health Administration, Greater Los Angeles Healthcare System, Los Angeles, California
3. National Clinician Scholars Program, University of California, Los Angeles, Los Angeles
4. RAND Corporation, Santa Monica, California
5. Center for Health Systems Research, Division of Research, Development and Dissemination, Sutter Health, Walnut Creek, California
6. Center for Health Systems Research, Palo Alto Medical Foundation Research Institute, Sutter Health, Palo Alto, California