[1] Soonchunhyang Univ, Cheonan, South Korea
[2] Korea Univ, Guro Hosp, Seoul, South Korea
[3] Natl Univ Boramae Hosp, Seoul, South Korea
[4] Eulji Gen Hosp, Seoul, South Korea
[5] Soon Chun Hyang Univ, Gumi Hosp, Gumi, South Korea
[6] Kangwon Natl Univ Hosp, Chunchon, South Korea