[1] Sungkyunkwan Univ, Kangbuk Samsung Hosp, Dept Med, Sch Med, Seoul, South Korea
[2] Hlth Insurance Review & Assessment Serv, Wonju, South Korea
[3] Sungkyunkwan Univ, Dept Med, Samsung Med Ctr, Sch Med, Seoul, South Korea
[4] Sungkyunkwan Univ, Dept Med Humanities, Samsung Med Ctr, Sch Med, Seoul, South Korea