1. Department of Health Sciences and Health PolicyUniversity of Lucerne Lucerne Switzerland
2. Childhood Cancer Research GroupDanish Cancer Society Research Center Copenhagen Denmark
3. School of Women's and Children's HealthUNSW Sydney NSW Australia
4. Kids Cancer CentreSydney Children's Hospital Randwick NSW Australia
5. Institute of Social and Preventive MedicineUniversity of Bern Bern Switzerland
6. University Children's Hospital Basel Basel Switzerland
7. Division of Paediatric Hematology/OncologyUniversity Children's Hospital BernInselspital Bern Switzerland
8. University Clinic of MedicineKantonsspital Baselland Liestal Switzerland