1. Hunter College, City University of New York, New York, USA
2. Harvard Medical School, Boston, Massachusetts, USA
3. Cambridge Health Alliance, Cambridge, Massachusetts, USA
4. Boston Medical Center, Crosstown Center, Boston, Massachusetts, USA
5. Boston University School of Medicine, Boston, Massachusetts, USA
6. Veterans Affairs Boston Healthcare System, Jamaica Plain, Massachusetts, USA
7. Boston University School of Public Health, Boston, Massachusetts, USA