1. Department of Pediatrics, Faculty of Medicine, Pham Ngoc Thach University of Medicine , 2 Duong Quang Trung Str., Dist. 10, 72500, Ho Chi Minh City , Vietnam
2. Department of Gastroenterology, Children's Hospital 2 , 14 Ly Tu Trong Str., Dist. 1, 71000, Ho Chi Minh City , Vietnam
3. Department of Family Medicine, Faculty of Medicine, Pham Ngoc Thach University of Medicine , 2 Duong Quang Trung Str., Dist. 10, 72500, Ho Chi Minh City , Vietnam
4. Pham Ngoc Thach University of Medicine , 2 Duong Quang Trung Str., Dist. 10, 72500, Ho Chi Minh City , Vietnam
5. Department of Epidemiology, Faculty of Public Health, Pham Ngoc Thach University of Medicine , 2 Duong Quang Trung Str., Dist. 10, 72500, Ho Chi Minh City , Vietnam