1. Faculty of Medicine, Department of Emergency Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand;
2. Faculty of Medicine, Ramathibodi Poison Center, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand;
3. Faculty of Medicine, Section for Clinical Epidemiology and Biostatistics, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand;
4. Faculty of Medicine, Department of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand