1. Department of Pediatrics; Aarhus University Hospital; Aarhus Denmark
2. Department of Woman and Child Health; Karolinska Institute; Stockholm Sweden
3. Department of Pediatric Medicines; Oslo University Hospital; Rikshospitalet Oslo Norway
4. Department of Clinical Sciences; Queen Silviás Childreńs Hospital; Gothenburg Sweden
5. Department of Oncology and Hematology; Tallinn Childreńs Hospital; Tallinn Estonia
6. Faculty of Medicine; Clinic of Childreńs Diseases; Vilnius University; Vilnius Lithuania
7. Pediatric Hematology-Oncology; Childreńs Hospital; Reykjavik Iceland
8. Department of Pediatric and Adolescent Medicine; Copenhagen University Hospital; Copenhagen Denmark
9. Faculty of Medicine; Institute of Clinical Medicine; University of Copenhagen; Copenhagen Denmark