Funding for this research was provided by:
Norges Teknisk-Naturvitenskapelige Universitet
Received: 5 April 2020
Accepted: 11 January 2021
First Online: 18 March 2021
Ethics approval and consent to participate
: Written informed consent was obtained from participants. In accordance with the Declaration of Helsinki, medical research ethical committees and data protection authorities from participating countries gave their approval according to national regulations (Dnr 2014/413–31 (Sweden), 1–10–72-280-13 (Denmark), REK 2012/2051 (Norway), 174/13/03/03/2014 (Finland)).
: Not applicable
: The authors declare that they have no competing interests.