Funding for this research was provided by:
Helse Vest (911846)
Received: 16 December 2019
Accepted: 20 May 2020
First Online: 19 June 2020
Ethics approval and consent to participate
: All participants provided voluntary and informed written consent to participate in the study. This study was approved by the Regional Committees for Medical and Health Research Ethics, REC West Norway (2016/34).
: Not applicable.
: The authors declare that they have no competing interests.