1. Department of Neurology and Neurophysiology; University Hospital of North Norway; Tromsø Norway
2. Department of Clinical Medicine; The Arctic University of Norway; Tromsø Norway
3. Institute of Neurosciences; Uppsala University; Uppsala Sweden
4. Department of Clinical Neurophysiology; Uppsala University Hospital; Uppsala Sweden
5. Department of Clinical Pathology; University Hospital of North Norway; Tromsø Norway
6. Department of Medical Biology; The Arctic University of Norway; Tromsø Norway
7. Department of Internal Medicine; University Hospital of North Norway; Tromsø Norway