1. Department of Family Medicine, Georgetown University Medical Center, Washington, DC.
2. Department of Medicine, Georgetown University Medical Center, Washington, DC.
3. Division of General Internal Medicine, Department of Medicine, Montefiore Medical Center, Bronx, NY.
4. City of Hope National Medical Center, Duarte, CA.
5. Clinical Pharmacy, Medicine and Epidemiology, University of California, San Francisco, CA.
6. SUNY Downstate Medical Center, Brooklyn, New York, NY.
7. The CORE Center at John H. Stroger Jr. Hospital of Cook County, Chicago, IL.
8. Epidemiology Branch, Basic Sciences Program, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD.