1 Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital Bergen, Norway ; Kristian Gerhard Jebsen Centre for MS Research, Department of Clinical Medicine, University of Bergen Bergen, Norway.
2 Department of Neurology, Oslo University Hospital Ullevål, Oslo, Norway.
3 Department of Neurology, Akershus University Hospital Lørenskog, Norway ; Institute of Clinical Medicine, University of Oslo Oslo, Norway.
4 Deptartment of Neurology, University Hospital of North Norway Tromsø, Norway.
5 Institute of Clinical Medicine, University of Oslo Oslo, Norway ; Innlandet Hospital Trust Lillehammer, Norway.
6 Department of Neurology, Molde Hospital Molde, Norway ; Unit for Applied Clinical Research, Norwegian University of Science and Technology Trondheim, Norway.
7 Department of Public Health and Primary Health Care, University of Bergen Bergen, Norway.