[1] Ewha Womans Univ, Dept Med Educ, Sch Med, Seoul 158710, South Korea
[2] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Pulm & Clin Care Med, Seoul, South Korea
[3] Natl Canc Ctr, Res Inst & Hosp, Canc Management Branch, Goyang, Gyeonggi, South Korea
[4] Dongguk Univ, Dept Med, Seoul, South Korea
[5] Seoul Natl Univ, Coll Med, Seoul Natl Univ Hosp, Dept Internal Med, Seoul, South Korea
[6] Ewha Womans Univ, Sch Law, Seoul 158710, South Korea
[7] Gunma Univ, Grad Sch Med, Gunma, Japan
[8] Chinese Acad Med Sci, Peking Union Med Coll, Res Ctr Bioeth, Beijing 100730, Peoples R China