1. Faculty of Medicine, Can Tho University of Medicine and Pharmacy, Can Tho 900000, Vietnam
2. Tra Vinh General Hospital, Tra Vinh 940000, Vietnam
3. Faculty of Medicine, Chulalongkorn University, 1873, Rama 4 Road, Pathumwan, Bangkok 10330, Thailand
4. Faculty of Health Sciences, Kanazawa University, Kanazawa 920-0942, Ishikawa, Japan