1. Pediatric Oncology and Hematology Department Vall d'Hebron Barcelona Hospital Barcelona Spain
2. Fundación de Investigación Biomédica Hospital 12 de Octubre Instituto de Investigación 12 de Octubre (imas12) Madrid Spain
3. Department of Pediatrics Infanta Sofía University Hospital Fundación para la Investigación Biomédica e Innovación Hospital Universitario Infanta Sofía y Hospital del Henares (FIIB HUIS HHEN) Madrid Spain
4. Universidad Europea de Madrid Madrid Spain
5. BioBizkaia Health Research Institute Pediatric Oncology Group Barakaldo Spain
6. UPV/EHU, Physiology Department Universidad del País Vasco/Euskal Herriko Unibertsitatea Leioa Spain
7. Pediatric Infectious Disease Unit Hospital Universitario 12 de Octubre Madrid Spain
8. Paediatrics Department Paediatric and Adolescent Haematology and Oncology Section Hospital Materno‐Infantil del Complejo Hospitalario General Universitario Gregorio Marañón Madrid Spain
9. Faculty of Medicine Universidad Complutense de Madrid Madrid Spain
10. Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM) Madrid Spain
11. Pediatric Oncology and Hematology Unit Hospital Sant Joan de Déu Barcelona Spain
12. Pediatric Oncology and Hematology Department Hospital Infantil Universitario La Paz Madrid Spain
13. Pediatric Oncology and Hematology Department Hospital Clínico Universitario de Valladolid Valladolid Spain
14. Pediatric Oncology and Hematology Department Hospital Infantil Infanta Leonor Almería Spain
15. Pediatric Oncology and Hematology Unit Hospital Infantil Universitario del Niño Jesús Madrid Spain
16. Hospital Doctor Balmis de Alicante Alicante Spain
17. Pediatric Oncology Unit Complejo Hospitalario de Toledo Toledo Spain
18. i+12 Research Institute Hospital 12 de Octubre Madrid Spain
19. Pediatric Oncology and Hematology Department Hospital Universitario Virgen de las Nieves Granada Spain
20. Hospital Clínico Universitario Valencia Valencia Spain
21. Pediatric Oncology and Hematology Unit HM Hospitals Madrid Spain
22. Paediatric Infectious Diseases Rheumatology and Immunology Department Hospital Universitario Virgen del Rocío Sevilla Spain
23. Congenital Alterations of Immunity Group Infectious Diseases and Immune System Area Instituto de Biomedicina de Sevilla Sevilla Spain
24. Pediatric Oncology and Hematology Unit Donostia University Hospital San Sebastián Spain
25. Biogipuzkoa Health Research Institute Pediatric Group, Paseo Dr. Begiristain San Sebastián Spain
26. UPV/EHU, Pediatric Department Paseo Dr. J. Beguiristain Universidad del País Vasco/Euskal Herriko Unibertsitatea San Sebastian Spain
27. Paediatrics Department Hospital Universitario Son Espases Mallorca Spain
28. Pediatric Oncology and Hematology Department Hospital Universitario de Burgos Burgos Spain
29. Pediatric Oncology and Hematology Department Hospital Universitario y Politécnico La Fe Valencia Spain
30. Paediatrics Department Hospital General de Albacete Albacete Spain
31. Paediatrics Department Complejo Asistencial de Segovia Segovia Spain
32. Hospital Álvaro Cunqueiro Vigo Spain
33. Pediatric Oncology and Hematology Department Hospital Universitario de Salamanca Salamanca Spain
34. Hospital Universitario Juan Ramón Jiménez Huelva Spain
35. Paediatrics Department Hospital Universitario de Canarias Tenerife Spain
36. Pediatric Infectious Diseases and Immunodeficiencies Unit Vall d'Hebron Institut de Recerca Universitat Autònoma de Barcelona Hospital Vall d'Hebron Barcelona Catalonia Spain
37. Unit of Statistics and Bioinformatics (UEB) Vall d'Hebron Research Institute (VHIR) Barcelona Spain
38. Department of Pediatrics Hospital Universitario Cruces Barakaldo Spain
39. UPV/EHU, Department of Pediatrics Universidad del País Vasco/Euskal Herriko Unibertsitatea Barakaldo Spain