1. Department of Global and Community Health, College of Public Health, George Mason University, Fairfax, VA 22030, USA
2. Heller School for Social Policy and Management, Brandeis University, Waltham, MA 02453, USA
3. INOVA Health System, Fairfax, VA 22031, USA
4. Department of Epidemiology and Biostatistics, School of Public Health, University of Maryland, College Park, MD 20742, USA
5. The Fenway Institute, Fenway Health, Boston, MA 02215, USA
6. Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
7. Harvard Medical School, Harvard University, Boston, MA 01451, USA
8. David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
9. Department of Behavioral and Community Health, School of Public Health, University of Maryland, College Park, MD 20742, USA