1. Department of Paediatric and Adolescent Medicine; Akershus University Hospital; Akershus Norway
2. Institute of Clinical Medicine; Campus Akershus University Hospital; University of Oslo; Oslo Norway
3. HØKH; Research Centre; Akershus University Hospital; Lørenskog Norway
4. Department of Paediatrics; University Hospital of North Norway; Tromsø Norway
5. Paediatric Research Group; Faculty of Health Sciences; University of Tromsø; Tromsø Norway