[1] Sungkyunkwan Univ, Sch Med, Dept Pediat, Samsung Changwon Hosp, 158 Paryong Ro, Chang Won 51353, South Korea
[2] Sungkyunkwan Univ, Sch Med, Dept Neurosurg, Samsung Changwon Hosp, Chang Won, South Korea
[3] Sungkyunkwan Univ, Sch Med, Dept Biostat, Samsung Changwon Hosp, Chang Won, South Korea