1. Clinical Addition Research and Education Unit,
2. Sections of General Internal Medicine and
3. Infectious Diseases, Department of Medicine, Boston University School of Medicine and
4. Grayken Center for Addiction, Boston Medical Center, Boston, Massachusetts
5. Institute for Research, Quality, and Policy in Homeless Health Care, Boston Health Care for the Homeless Program, Boston, Massachusetts;
6. Division of General Pediatrics, Department of Pediatrics, School of Medicine, Boston University and Grayken Center for Addiction, Boston Medical Center, Boston, Massachusetts; and
7. Department of Epidemiology, School of Public Health, Brown University, Providence, Rhode Island