[1] Catholic Univ Korea, Seoul St Marys Hosp, Coll Med, Dept Emergency Med, 222 Banpo Daero, Seoul 06591, South Korea
[2] Catholic Univ Korea, Eunpyeong St Marys Hosp, Coll Med, Dept Emergency Med, Seoul, South Korea
[3] Catholic Univ Korea, Uijeongbu St Marys Hosp, Coll Med, Dept Emergency Med, Seoul, South Korea
[4] Catholic Univ Korea, St Vincents Hosp, Coll Med, Dept Emergency Med, Seoul, South Korea
[5] Ulsan Univ, Asan Med Ctr, Dept Emergency Med, Coll Med, Seoul, South Korea
[6] Chonnam Natl Univ Hosp, Dept Emergency Med, Gwangju, South Korea
[7] Vet Hlth Serv Med Ctr, Dept Emergency Med, Seoul, South Korea