| Affiliation: | 1. Swiss Childhood Cancer Registry, Institute of Social and Preventive Medicine, University of Bern, Switzerland;2. Department of Pediatric Oncology/Hematology, University Children's Hospital Basel, University of Basel, Switzerland;3. Department for Epidemiology and Preventive Medicine/Medicine Sociology, University of Regensburg, Germany;4. Pediatric Respiratory Medicine, Inselspital, Bern University Hospital, University of Bern, Switzerland;5. Department of Pediatrics, Oncology and Hematology Unit, Geneva University Hospital, Switzerland |
