Funding for this research was provided by:
Norges Forskningsråd (214187/F20)
Universitetet i Bergen (214187/F20)
Helse Vest (912148)
Received: 11 December 2018
Accepted: 4 April 2019
First Online: 1 June 2019
Ethics approval and consent to participate
: Patients gave their written informed consent under institutional review board-approved protocols (Rek Vest project #19297 and #13025 and 273/96-82.96).
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: The authors declare that they have no competing interests.
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