1. Department of Research and Development, Clinic of Substance Use and Addiction Medicine, St. Olavs University Hospital, Trondheim, Norway
2. Department of Public Health and Nursing, NTNU Norwegian University of Science and Technology, Trondheim, Norway
3. Department of Addiction Treatment, Oslo University Hospital, Oslo, Norway
4. Department of Substance Abuse Treatment, Clinic of Mental Health and Substance Abuse Treatment, Møre og Romsdal Hospital Trust, Ålesund, Norway