1. National Institute of Hygiene and Epidemiology, Hanoi, Vietnam;
2. School of Public Health, Curtin University, Perth, Australia;
3. Department of Epidemiology, Faculty of Public Health, Thai Nguyen University of Medicine and Pharmacy, Thai Nguyen, Vietnam;
4. Department of Nutrition and Food, Faculty of Public Health, University of Medicine and Pharmacy, Ho Chi Minh City, Vietnam;
5. Department of Environmental and Occupational Health, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam;
6. Department of Epidemiology, Faculty of Public Health, Hai Phong University of Medicine and Pharmacy, Hai Phong, Vietnam;
7. United Nations Population Fund, Hanoi, Vietnam