Received: 19 August 2018
Accepted: 25 February 2019
First Online: 8 March 2019
: TB is a medical doctor.NEG is a specialist in neurology the Haukeland University Hospital, Bergen, Norway and professor at the University of Bergen, Norway.TR is a specialist in neurology at the Haukeland University Hospital, Bergen, Norway and professor at the Sahlgrenska Academy, University of Gothenburg, Sweden.
: The project has been evaluated before the start at the University of Bergen and Haukeland University Hospital. No interventions have been performed related to this project.
: Individual data have not been used for this manuscript.
: The authors declare that they have no competing interests.
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