1. Department of Neurology; St Olavs Hospital; Trondheim University Hospital; Trondheim Norway
2. Department of Neuroscience; Norwegian University of Science and Technology (NTNU); Trondheim Norway
3. Department of Neurosurgery; St. Olavs Hospital; Trondheim University Hospital; Trondheim Norway
4. The Norwegian Patient Registry; Trondheim Norway
5. Department of Public Health and General Practice; Norwegian University of Science and Technology (NTNU); Trondheim Norway