1. Department of Psychiatry and Behavioral Medicine, Center
for AIDS Intervention Research, Medical College of Wisconsin, Milwaukee, USA,
2. Department of Psychiatry and Behavioral Medicine, Center
for AIDS Intervention Research, Medical College of Wisconsin, Milwaukee, USA
3. HIV Epidemiology Section, San Francisco Department of
Public Health, CA, USA
4. Division of STD Prevention, Centers for Disease Control
and Prevention, Atlanta, GA, USA