1. Center for Health Services Research in Primary Care, Durham Veterans Affairs Medical Center, Durham, North Carolina
2. Department of Population Health Sciences, Duke University School of Medicine, Durham, North Carolina
3. Division of General Internal Medicine, Department of Medicine, Duke University School of Medicine, Durham, North Carolina
4. The Comparative Health Outcomes, Policy, and Economics (CHOICE) Institute, Departments of Pharmacy, Health Services, and Economics, University of Washington, Seattle