[1] Chiba Univ, Grad Sch Med, Dept Pediat Surg, Chiba, Japan
[2] Univ Tokyo, Dept Healthcare Qual Assessment, Grad Sch Med, Tokyo, Japan
[3] Translat Med Ctr Natl Ctr Neurol & Psychiat, Tokyo, Japan
[4] Bur Int Hlth Cooperat, Inst Global Hlth Policy Res, Natl Ctr Global Hlth & Med, Tokyo, Japan
[5] Univ Tokyo, Dept Pediat Surg, Grad Sch Med, Tokyo, Japan
[6] Tokyo Metropolitan Childrens Med Ctr, Dept Surg, Tokyo, Japan
[7] Kyoto Univ, Dept Hepatobiliary Pancreat Surg & Transplantat, Grad Sch Med, Kyoto, Japan
[8] Hyogo Prefectural Amagasaki Gen Med Ctr, Dept Pediat Surg, Amagasaki, Hyogo, Japan
[9] Kindai Univ, Dept Pediat Surg, Sch Med, Nara Hosp, Nara, Japan
[10] Osaka Womens & Childrens Hosp, Dept Pediat Surg, Izumi, Japan
[11] Japanese Soc Pediat Surg, Natl Clin Database Comm, Tokyo, Japan
[12] Japanese Soc Pediat Surg, Pediat Surg Database Comm, Tokyo, Japan