1. Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
2. Department of Pediatric Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan
3. Department of Pediatric Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
4. Division of Neonatology, Department of Maternal and Perinatal Medicine, National Center for Child Health and Development, Tokyo, Japan
5. Division of Neonatology, Center for Maternal-Neonatal Care, Nagoya University Hospital, Nagoya, Japan
6. Department of Pediatric Surgery, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan
7. Department of Pediatric Surgery, Kobe Children's Hospital, Kobe, Japan
8. Department of Pediatric Surgery, Hyogo College of Medicine, Nishinomiya, Japan
9. Department of Pediatric Surgery, Kyushu University, Fukuoka, Japan