1. Department of Paediatric Habilitation, Stavanger University Hospital, Stavanger, Norway
2. Department of Pediatrics, Sørlandet Hospital, Arendal, Norway
3. Department of Clinical and Laboratory Medicine, Norwegian University of Science and Technology, Trondheim, Norway
4. Cerebral Palsy Register of Norway, Habilitation Center, Vestfold Hospital Trust, Tønsberg, Norway
5. Department of Child and Adolescent Psychiatry, Vestfold Hospital Trust, Tønsberg, Norway