1. Department of Emergency Medicine, Soonchunhyang University Hospital , Bucheon , Republic of Korea
2. Department of Emergency Medicine, Dong-A University Hospital, College of Medicine , Busan , Republic of Korea
3. Department of Emergency Medicine, Soonchunhyang University Hospital , Cheonan , Republic of Korea
4. Department of Biostatistics, Clinical Trial Center, Soonchunhyang University Bucheon Hospital , Bucheon 14584 , Republic of Korea