Funding for this research was provided by:
Foundation for Chiropractic and Clinical Biomechanics, Denmark.
Received: 8 October 2018
Accepted: 26 February 2019
First Online: 1 May 2019
: Information on authors qualifications and affiliations is found on the first page of this article.
: Not applicable. This study was done in conjunction with quality assurance procedures required by Danish law [CitationRef removed] and all personal data were blinded for the observers. Only documentation of image quality was performed, with no possible correlation to patients. The procedures are mandatory and has no consequences for diagnoses and treatment of patients.
: Not applicable.
: The authors declare that they have no competing interests.
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