1. Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
2. Centre of Excellence for Research in AIDS (CERiA), University of Malaya, Kuala Lumpur, Malaysia
3. AIDS Program, Yale School of Medicine, New Haven, CT, USA
4. Department of Biostatistics and Epidemiology, School of Public Health, University of North Texas Health Science Center, Fort Worth, TX, USA
5. Department of Primary Care Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia