1. Department of Psychiatry, Helse Fonna HF, Haugesund, Norway;
2. Academic Unit of Child and Adolescent Psychiatry, Imperial College, St Mary’s Campus, London, United Kingdom;
3. Center for Clinical Research, Helse Bergen HF, Bergen, Norway;
4. Division of Mental Health, Norwegian Institute of Public Health, Oslo; and
5. Health Services Research Centre, Akershus University Hospital, Akershus, Norway