1. Department of Surgical Sciences; Uppsala University Hospital; Uppsala Sweden
2. Department of Public Health and Caring Sciences; Uppsala University; Uppsala Sweden
3. Department of Anaesthesia; Skaraborg Hospital; Skövde Sweden
4. Department of Health Sciences; University West; Trollhättan Sweden
5. Faculty of Professional Studies; University of Nordland; Bodø Norway
6. Department of Clinical Neuroscience; Karolinska Institutet; Stockholm Sweden
7. Department of Neurosurgery, R2:02; Karolinska University Hospital; Stockholm Sweden