1. Department of Family Medicine, Georgetown University Medical Center, Washington, District of Columbia
2. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
3. State University of New York Downstate Medical Center, Brooklyn, New York
4. John H. Stroger 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, District of Columbia