1. Department of Family Medicine, Georgetown University Medical Center, Washington, D.C.
2. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
3. SUNY Downstate Medical Center, Brooklyn, New York.
4. The CORE Center at John H. Stroger Jr. Hospital of Cook County, Chicago, Illinois.
5. Montefiore Medical Center, Bronx, New York.
6. Department of Medicine, University of California, San Francisco, San Francisco, California.
7. Keck School of Medicine, University of Southern California, Los Angeles, California.
8. Department of Medicine, Georgetown University Medical Center, Washington, D.C.