1. Department of Social and Behavioral Sciences, Yale School of Public Health, New Haven, Connecticut, USA.
2. Center for Interdisciplinary Research on AIDS, Yale School of Public Health, New Haven, Connecticut, USA.
3. Positive Impact Health Centers, Atlanta, Georgia, USA.
4. Children's Hospital Los Angeles, Los Angeles, California, USA.
5. Institute for Health Research and Policy, The University of Illinois at Chicago, Chicago, Illinois, USA.