1. Centre for Training and Research on Substance use and HIV Hanoi Medical University Hanoi Vietnam
2. Faculty of Public Health University of Medicine and Pharmacy at Ho Chi Minh City Ho Chi Minh City Vietnam
3. Global Health Department Hanoi Medical University Hanoi Vietnam
4. Friends Research Institute, Friends Community Center, Center for HIV Identification, Prevention and Treatment Services University of California Los Angeles California USA
5. Center for Behavioral and Addiction Medicine, Department of Family Medicine University of California Los Angeles California USA