1. Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
2. The Danish Multiple Sclerosis Registry, Department of Neurology, Copenhagen University Hospital–Rigshospitalet, Copenhagen, Denmark
3. Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital–Rigshospitalet, Copenhagen, Denmark
4. Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
5. Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden
6. Department of Neurology, Aarhus University Hospital, Aarhus, Denmark
7. Multiple Sclerosis Clinic Southern Denmark, Department of Brain and Nerve Diseases, University of Southern Denmark, Odense, Denmark
8. Department of Brain & Nerve Diseases, Hospital of Southern Jutland, Odense, Denmark
9. Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden
10. Department of Neurology, Sahlgrenska University Hospital, Gothenburg, Sweden