1. Department of Medical Biosciences; Umeå University; Umeå Sweden
2. Department of Radiation Sciences; Umeå University; Umeå Sweden
3. Department of Paediatrics and Adolescent Medicine; Rigshospitalet; Copenhagen Denmark
4. Department of Pediatrics; University of Tromsø and University Hospital of North Norway; Tromsø Norway
5. Children’s Hospital, Helsinki University Central Hospital, University of Helsinki; Helsinki Finland
6. Department of Women’s and Children’s Health; Karolinska Institutet; Stockholm Sweden