1. Department of Pediatrics and Adolescent Medicine Aarhus University Hospital Aarhus Denmark
2. Department of Clinical Medicine, Faculty of Health Aarhus University and University Hospital Aarhus Denmark
3. Unit of Statistics and Data Analysis Danish Cancer Society Research Center Copenhagen Denmark
4. Childhood Cancer Research Group Danish Cancer Society Research Center Copenhagen Denmark
5. Division of Childhood Cancer Epidemiology, Institute of Medical Biostatistics, Epidemiology and Informatics University Medical Center of the Johannes Gutenberg University Mainz Mainz Germany
6. Unit of Epidemiology, Institute of Environmental Medicine Karolinska Institutet Stockholm Sweden
7. Department of Clinical Sciences Lund University, Pediatric Oncology and Hematology, Skåne University Hospital Lund Sweden
8. Finnish Cancer Registry Helsinki Finland
9. Childhood Cancer Research Unit, Department of Women's and Children's Health Karolinska Institutet Stockholm Sweden
10. Institute of Clinical Medicine, Faculty of Medicine University of Copenhagen Copenhagen Denmark