1. The Cerebral Palsy Registry of NorwayVestfold Hospital Trust Tønsberg Norway
2. Orthopedics Department of Clinical Sciences Skåne University HospitalLund University Lund Sweden
3. Royal Hospital for Sick Children Edinburgh UK
4. Centre for Alcohol and Drug Research Aarhus University Aarhus Denmark
5. Regional Centre for Child and Youth Mental Health and Child Welfare Department of Mental Health Norwegian University of Science and Technology Trondheim Norway