Funding for this research was provided by:
European Chiropractors Union (A.13.04)
Stiftelsen Sigurd and Elsa Goljes Minne (LA2016-0356)
Västerbotten Läns Landsting
Medicinska fakulteten, Umeå Universitet (Personal grant professorship)
Article History
Received: 28 December 2018
Accepted: 10 May 2019
First Online: 13 August 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee at the Umeå University (Dnr 2014–4-32 M supplement to Dnr 2012–404-31 M) and was performed in accordance with the Declaration of Helsinki. Written informed consent was obtained from all participants. No collection of details, images, or videos related to an individual person took place in this study.
: Not applicable in this study.
: The authors declare that they have no competing interests.
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