[1] Chung Ang Univ Hosp, Dept Emergency Med, Seoul, South Korea
[2] Chung Ang Univ, Coll Med, Dept Emergency Med, Seoul, South Korea
[3] Hallym Univ, Dept Emergency Med, Dongtan Sacred Heart Hosp, Hwaseong, South Korea
[4] Catholic Univ Korea, Coll Med, Dept Emergency Med, Seoul, South Korea
[5] Eulji Univ, Dept Emergency Med, Seoul, South Korea
[6] CHA Univ, CHA Bundang Med Ctr, Dept Emergency Med, Seongnam Si, Gyeonggi Do, South Korea
[7] Seoul St Marys Hosp, Dept Emergency Med, Seoul, South Korea
[8] Soonchunhyang Univ, Dept Emergency Med, Bucheon Hosp, Bucheon, South Korea
[9] Ewha Womans Univ, Ewha Womans Univ Mokdong Hosp, Coll Med, Dept Emergency Med, Seoul, South Korea