Funding for this research was provided by:
Helse Vest Regionalt Helseføretak
Received: 24 November 2017
Accepted: 19 December 2018
First Online: 18 January 2019
Ethics approval and consent to participate
: All patients have signed an informed consent form.The protocol has been approved by the Norwegian Committee for Medical and Health Research Ethics Midt (2014/344).
: Not applicable.
: None of the authors have any conflicts of interest.
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