Funding for this research was provided by:
Norges Forskningsråd (256681/H10)
Received: 31 October 2019
Accepted: 20 January 2021
First Online: 30 January 2021
Ethics approval and consent to participate
: The Regional Committees for Research Ethics in Norway considered that the study was not governed by the Health Research Act. The Norwegian Social Science Data Services approved the study in two phases (Phase 1: NSD, ID 52324; Phase 2: NSD, ID 54855). The study followed the Helsinki Declaration, and all participants gave individual informed written consent to take part in the study.
: Not applicable.
: Author SW is associate editor of BMC Health Services Research. The other authors declare that they have no competing interests.