1. Center for Health Care Evaluation, VA Palo Alto Health Care System, Menlo Park, California.
2. Division of General Internal Medicine, Stanford University School of Medicine, Palo Alto, California.
3. Center for Health Policy and Center for Primary Care and Outcomes Research, Stanford University School of Medicine, Palo Alto, California.
4. Women's Health Center, VA Palo Alto Health Care System, Palo Alto, California.
5. Health Economics Resource Center, VA Palo Alto Health Care System, Menlo Park, California.
6. VA Greater Los Angeles HSR&D Center for the Study of Healthcare Provider Behavior, Sepulveda, California.
7. Department of Health Services, UCLA School of Public Health, Los Angeles, California.
8. Department of Health Research and Policy and Department of Pediatrics, Stanford University School of Medicine, Palo Alto, California.