Funding for this research was provided by:
National Institute of Neurological Disorders and Stroke (U01 NS097028, R01 NS064934, R21 NS097643)
Received: 29 September 2017
Accepted: 8 November 2017
First Online: 22 November 2017
Ethics approval and consent to participate
: All protocols were approved by the local Institutional Review Boards, and all participants were recruited and consented to participate in the outpatient clinic of the Department of Neurology, St. Olavs hospital, Trondheim, Norway
: Not applicable.
: TY and OSM are employees of Biogen Inc. The authors declare no other competing financial or non-financial interests.
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