1. Center for HIV Identification, Prevention and Treatment Services
2. Department of Family Medicine
3. Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles
4. Division of HIV and STD Programs, Los Angeles County Department of Public Health
5. Division of General Internal Medicine and Health Services Research
6. Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California, USA.