[1] Inje Univ, Coll Med, Busan Paik Hosp, Dept Pediat, Busan, South Korea
[2] Univ Ulsan, Coll Med, Dept Pediat, Asan Med Ctr,Childrens Hosp, 88 Olymp Ro 43 Gil, Seoul 05505, South Korea
[3] Univ Ulsan, Coll Med, Pediat Surg, Asan Med Ctr,Childrens Hosp, Seoul, South Korea
[4] Univ Ulsan, Coll Med, Asan Med Ctr, Hlth Screening & Promot Ctr, Seoul, South Korea
[5] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Gastroenterol, Seoul, South Korea