[1] Yonsei Univ, Severance Hosp, Coll Med, Dept Internal Med, Seoul, South Korea
[2] Anam Hosp, Univ Coll Med, Dept Internal Med, Seoul, South Korea
[3] Ajou Univ, Ajou Univ Hosp, Sch Med, Dept Pulm & Crit Care Med, Suwon, South Korea
[4] Sungkyunkwan Univ, Kangbuk Samsung Hosp, Sch Med, Dept Internal Med, Seoul, South Korea
[5] Gachon Univ, Gil Med Ctr, Sch Med, Dept Internal Med, Incheon, South Korea
[6] Yonsei Univ, Gangnam Severance Hosp, Coll Med, Dept Internal Med, Seoul, South Korea
[7] Ewha Womans Univ, Mok Dong Hosp, Sch Med, Dept Internal Med, Seoul, South Korea
[8] Sungkyunkwan Univ, Samsung Med Ctr, Sch Med, Dept Internal Med, Seoul, South Korea
[9] Yonsei Univ, Wonju Christian Hosp, Wonju Coll Med, Dept Internal Med, Wonju, South Korea
[10] Hallym Univ, Sacred Heart Hosp, Coll Med, Dept Internal Med, Anyang, South Korea
[11] Korea Univ, Ansan Hosp, Coll Med, Dept Internal Med, Ansan, South Korea
[12] Konyang Univ, Konyang Univ Hosp, Coll Med, Dept Internal Med, Daejeon, South Korea
[13] Hanil Gen Hosp, Dept Internal Med, Seoul, South Korea