1. Department of Emergency Medicine, Chungbuk National University Hospital, Seowon-gu, Cheongju-si, Chungcheongbuk-do, South Korea;
2. Department of Emergency Medicine, Seoul National University Hospital, Jongno-gu, Seoul, South Korea;
3. Department of Emergency Medicine, School of Medicine, Chungnam National University, Chungnam National University Hospital, Jung-gu, Daejeon, Chungcheongnam-do, South Korea;
4. Department of Emergency Medical Technology, Choonhae College of Health Sciences, Ungchon-myeon, Ulju-gun, Ulsan, South Korea;
5. Korea Centers for Disease Control and Prevention, Osong-eup, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, South Korea