1. Department of PediatricsYamagata University Hospital Yamagata Japan
2. Department of PediatricsHiroshima Red Cross Hospital and Atomic‐bomb Survivors Hospital Hiroshima Japan
3. Department of Pediatric Medicine for Hospital CollaborationGraduate School of Medical SciencesKyushu University Fukuoka Japan
4. Department of PediatricsYamaguchi University Graduate School of Medicine Ube Japan
5. Children's Cancer CenterNational Center for Child Health and Development Tokyo Japan
6. Department of Hematology and OncologyChildren's Medical CenterJapanese Red Cross Nagoya First Hospital Nagoya Japan
7. Department of Hematology/OncologySaitama Children's Medical Center Saitama Japan
8. Department of Hematology and OncologyChiba Children's Hospital Chiba Japan
9. Department of Hematology/OncologyOsaka Medical Center and Research Institute for Maternal and Child Health Osaka Japan
10. Department of Hematopoietic Stem Cell TransplantationNational Cancer Center Hospital Tokyo Japan
11. Department of Cell Transplantation and Regenerative MedicineTokai University School of Medicine Kanagawa Japan
12. Department of PediatricsKyoto University Hospital Kyoto Japan
13. Department of PediatricsOkayama University Hospital Okayama Japan
14. Department of PediatricsOsaka University Graduate School of Medicine Osaka Japan
15. Department of Hematology/OncologyMiyagi Children's Hospital Sendai Japan
16. Japanese Data Center for Hematopoietic Cell TransplantationDepartment of Healthcare AdministrationNagoya University Graduate School of Medicine Nagoya Japan
17. Division of HematologyJichi Medical UniversitySaitama Medical Center Saitama Japan
18. Innovative Cancer Center/Oncology‐HematologyShimane University Hospital Cancer Center Izumo Japan
19. Department of PediatricsSapporo Hokuyu Hospital Sapporo Japan