1. Department of Neurology, Akershus University Hospital , Lørenskog, Norway
2. Institute of Clinical Medicine, University of Oslo , Oslo, Norway
3. Department of Physical Health and Ageing, Norwegian Institute of Public Health , Oslo, Norway
4. Department of Community Medicine and Global Health, University of Oslo , Oslo, Norway
5. Department of Clinical Medicine, University of Bergen , Bergen, Norway
6. Neuro-SysMed, Department of Neurology, Haukeland University Hospital , Bergen, Norway