Funding for this research was provided by:
University of Bergen
Article History
Received: 17 November 2017
Revised: 1 February 2018
Accepted: 22 February 2018
First Online: 21 March 2018
Ethics approval and consent to participate
: The protocol was reviewed and approved by the Ethical Research Committee at the University of Bergen, Norway (2009/610REK vest). The purpose of the study was explained to the patients and written informed consent was obtained.
: Not applicable.
: The authors declare that they have no competing interests.
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