[1] Sungkyunkwan Univ, Sch Med, Dept Endocrinol & Metab, Kangbuk Samsung Hosp, Seoul, South Korea
[2] Sungkyunkwan Univ, Sch Med, Dept Lab Med, Kangbuk Samsung Hosp, Seoul, South Korea
[3] Sungkyunkwan Univ, Sch Med, Changwon Samsung Hosp, Dept Lab Med, Chang Won, South Korea
[4] Sungkyunkwan Univ, Sch Med, Dept Ophthalmol, Kangbuk Samsung Hosp, Seoul, South Korea
[5] Dongguk Univ, Dept Stat, Seoul, South Korea