1. Centre for Epidemiology and Evidence-Based Practice, Department of Social and Preventive Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
2. Department of Social and Preventive Medicine, Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia
3. Centre of Excellence for Research in AIDS (CERiA), Faculty of Medicine, Universiti Malaya, Kuala Lumpur 50603, Malaysia