1. Division of Mental and Physical Health Norwegian Institute of Public Health Oslo Norway
2. Promenta Research Center University of Oslo Oslo Norway
3. Norwegian Centre for Addiction Research (SERAF) Institute of Clinical Medicine, University of Oslo Oslo Norway
4. Department of Chronic Diseases Norwegian Institute of Public Health Oslo Norway
5. Centre for Alcohol and Drug Research (KORFOR) Stavanger University Hospital Stavanger Norway
6. Faculty of Health Sciences University of Stavanger Stavanger Norway
7. Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences Norwegian University of Science and Technology Trondheim Norway
8. Department of Pain and Complex Disorders St. Olav's University Hospital Trondheim Norway