1. 1Department of Pediatrics, Dr. von Hauner Children’s Hospital, University Hospital, Ludwig-Maximilians-Universität, Munich, Germany
2. 2Statistical Unit and Data Office, European Society for Blood and Marrow Transplantation (EBMT), Leiden, The Netherlands
3. 3Institute for Immunodeficiency, Center for Chronic Immunodeficiency, Faculty of Medicine, University of Freiburg, Freiburg, Germany
4. 4Department of Medicine I, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
5. 5Department of Adult Hematology, Necker-Enfants Malades University Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
6. 6Department of Hematology, Hospital Universitari Vall d’Hebron, Experimental Hematology, Vall d’Hebron Institute of Oncology (VHIO), Vall d’Hebron Hospital Campus, Barcelona, Spain
7. 7Pediatric Immuno-Hematology and Rheumatology Unit, Necker-Enfants University Hospital and French National Reference Center for Primary Immunodeficiencies (CEREDIH), AP-HP, Paris, France
8. 8Department of Pediatric Immunology & Haematopoietic Stem Cell Transplantation (HSCT), Great North Children’s Hospital, Newcastle upon Tyne, United Kingdom
9. 9Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
10. 10Department of Pediatrics, Pediatric Stem Cell Transplantation Program, Willem-Alexander Children’s Hospital, Leiden University Medical Center, Leiden, The Netherlands
11. 11Department of Pediatric Hematology and Oncology, Medizinische Hochschule Hannover (MHH), Hannover, Germany
12. 12Department of Pediatric Immunohematology, Istituto Di Ricovero e Cura a Carattere Scientifico (IRCCS) Ospedale San Raffaele, Milan, Italy
13. 13Northern Center for Cancer Care, Newcastle upon Tyne Hospitals National Health Service (NHS) Foundation Trust, Newcastle upon Tyne, United Kingdom
14. 14Department of Pediatric Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
15. 15Department of Pediatric Blood and Bone Marrow Transplantation, Princess Maxima Center, Utrecht, The Netherlands
16. 16Department of Immunology, Royal Free London Hospitals NHS Foundation Trust, London, United Kingdom
17. 17Institute of Immunity and Transplantation, University College London (UCL), London, United Kingdom
18. 18Department of Clinical Hematology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
19. 19Department of Hematology and Cellular Transplantation, Lower Silesian Center of Oncology, Wroclaw, Poland
20. 20Department of Hematology/Oncology/Immunology, Gene-Therapy, and Stem Cell Transplantation, University Children's Hospital Zurich – Eleonore Foundation & Children's Research Center (CRC), Zürich, Switzerland
21. 21Department of Hematopoietic Stem Cell Transplantation, Dmitriy Rogachev National Center for Pediatric Hematology, Oncology, and Immunology, Moscow, Russian Federation
22. 22Division of Pediatric Stem Cell Therapy, Department of Paediatric Oncology, Hematology and Clinical Immunology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
23. 23Department of Pediatric Immunology, Hematology, and Rheumatology, Necker-Enfants Malades University Hospital, AP-HP, Paris, France
24. 24Department of Pediatrics, University Medical Center Ulm, Ulm, Germany
25. 25Department of Pediatric Hematology and Oncology, Center for Pediatrics and Adolescent Medicine, Faculty of Medicine, University of Freiburg, Freiburg, Germany
26. 26Department of Pediatrics, Bone Marrow Transplantation (BMT) Unit, Hacettepe University, Faculty of Medicine, Ankara, Turkey
27. 27Department of Pediatrics, University Hospitals Leuven, Leuven, Belgium
28. 28Department of Microbiology, Immunology, and Transplantation, Katholieke Universiteit (KU) Leuven, Leuven, Belgium
29. 29Blood and Marrow Transplant Program, Royal Manchester Children’s Hospital, Manchester, United Kingdom