aDepartment of Rehabilitation Science and Health Technology, Faculty of Health Science, OsloMet—Oslo Metropolitan University, Oslo, Norway

bResearch and Communication Unit for Musculoskeletal Health (FORMI), Division of Clinical Neuroscience, Oslo University Hospital, Oslo, Norway

cDepartment of General Practice, Erasmus MC, University Medical Center, Rotterdam, the Netherlands

dCenter for Muscle and Health, University of Southern Denmark, Odense, Denmark

*Corresponding author. Address: OsloMet—Oslo Metropolitan University, Post Box 4, St. Olavs Plass, 0130 Oslo, Norway. Tel.: +47 414 59 314. E-mail address: [email protected] (Ø. N. Vigdal).

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