Funding for this research was provided by:
Helse- og Omsorgsdepartementet (10/1263)
Received: 21 November 2019
Accepted: 29 March 2020
First Online: 10 April 2020
Ethics approval and consent to participate
: The regional committee for medical and health research ethics of the University of Tromsø, Norway, approved the study (2012/1902/REK Nord). All participants provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.