Funding for this research was provided by:
Seventh Framework Programme (607510)
Received: 2 November 2017
Accepted: 15 February 2018
First Online: 23 February 2018
Ethics approval and consent to participate
: The study was reviewed and accepted by the Ethik Komission der Ärztekammer Westfalen-Lippe und der Westfälischen Wilhelms-Universität (‘2015–475-f-S’). All participants provided written informed consent prior to the study.
: Not applicable.
: Dieter Rosenbaum is a member of the editorial board of BMC Musculoskeletal Disorders. The remaining authors declare that they have no competing interests.
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