[1] Ewha Womans Univ, Dept Internal Med, Div Pulm & Crit Care Med, Seoul, South Korea
[2] Ewha Womans Univ, Med Ctr, Informatizat Dept, Seoul, South Korea
[3] Catholic Univ Korea, Seoul St Marys Hosp, Coll Med,Dept Internal Med, Div Pulm & Crit Care Med, Seoul, South Korea
[4] Hallym Univ, Dept Internal Med, Sacred Heart Hosp, Div Pulm Allergy & Crit Care Med, Anyang Si, South Korea
[5] Konkuk Univ Hosp, Dept Internal Med, Div Pulm & Allergy, Sch Med, Seoul, South Korea