1. Department of Paediatrics and Adolescent Medicine Aarhus University Hospital Aarhus Denmark
2. Department of Paediatric Oncology Karolinska University Hospital StockholmSweden
3. Childhood Cancer Research Unit Department of Women´s and Children´s Health Karolinska Institutet Stockholm Sweden
4. Children’s Hospital Landspitali University Hospital Reykjavik Iceland
5. Department of Paediatric and Adolescent Haematology/Oncology Turku University Hospital FICAN‐West Turku University Turku Finland
6. Department of Paediatrics University of Tromsø and University Hospital of North Norway Tromsø Norway
7. Department of Paediatrics and Adolescent Medicine Copenhagen University Hospital CopenhagenDenmark
8. Institute of Clinical Medicine Faculty of Health and Medical Sciences University of Copenhagen CopenhagenDenmark
9. Research Unit for General Practice Department of Public Health Aarhus University Aarhus Denmark