Funding for this research was provided by:
Norges Forskningsråd (no. 269855)
Helse Vest (Åpen prosjektstøtte)
Received: 22 June 2020
Accepted: 25 August 2020
First Online: 3 September 2020
Ethics approval and consent to participate
: The study was approved by the Regional committee for medical and health research ethics (no. 2017/51/REK vest). It was conducted in accordance with the Helsinki Declaration and STROBE guidelines All included participants signed a written consent to partake in the study.
: Not applicable. No personal details on any of the participants are reported in the manuscript, tables or figures.
: None of the authors have competing interests.