1. Emma Children’s Hospital Amsterdam UMC Vrije Universiteit AmsterdamPediatric oncology Amsterdam The Netherlands
2. Princess Máxima Center for Pediatric Oncology Utrecht The Netherlands
3. Emma Children’s Hospital Amsterdam UMC Amsterdam Medical CenterPediatric Oncology Amsterdam The Netherlands
4. Department of Epidemiology and Biostatistics Amsterdam UMC Vrije Universiteit Amsterdam Amsterdam The Netherlands
5. Department of Pediatric Hemato‐Oncology UZ Leuven Leuven Belgium
6. Department of Pediatrics Clinique MontLégiaCHC Liège Belgium
7. Department of Pediatric Onco‐Hematology Universitair Ziekenhuis Brussel Brussels Belgium
8. Department of Paediatric Haematology‐Oncology and Stem Cell Transplantation Ghent University Hospital Ghent Belgium