1. Department of Paediatrics; The University Hospital Rigshospitalet; Copenhagen; Denmark
2. Department of Paediatrics; The Queen Silvia Children's Hospital; Sahlgrenska University Hospital; Gothenburg; Sweden
3. Department of Clinical Science; Intervention and Technology; Karolinska Institutet, Karolinska University Hospital; Huddinge; Sweden
4. Department of Paediatrics; Queen Mary Hospital and Hong Kong Paediatric Haematology & Oncology Study Group (HKPHOSG); Hong Kong; China
5. Department of Paediatrics; University Hospital Lund; Lund; Sweden
6. Division of Haematology-Oncology and Stem Cell Transplantation; Children's Hospital; University of Helsinki; Helsinki University Central Hospital; Helsinki; Finland
7. Children's Hospital Iceland; Landspítali - University Hospital; Reykjavík; Iceland
8. Department of Women's and Children's Health; University Children's Hospital; Uppsala; Sweden
9. Department of Paediatrics; Oslo University Hospital Rikshospitalet; Oslo; Norway
10. Department of Paediatrics; Aarhus University Hospital Skejby; Aarhus; Denmark