Study design and setting
This retrospective cross-sectional study was conducted after the approval of The Committee on Human Rights Related to Research, Faculty of Medicine, Ramathibodi Hospital, Mahidol University review board using the data at Ramathibodi Hospital, Mahidol University, Bangkok, Thailand from January 2018 to June 2018. Ramathibodi Hospital is a medical school with 1,300 beds, 5,000 OPD visits per day, and approximately 60,000 emergency room visits per year.