Funding for this research was provided by:
Nasjonalforeningen for Folkehelsen
Received: 15 December 2020
Accepted: 1 April 2021
First Online: 21 April 2021
: The study was approved by the Regional Medical and Health Ethics Committee of Southeastern Norway (REK), with reference # 2017/1741. All participants received written information about the study, gave written consent and were informed about their ability to withdraw from the study at any time before publication of results.
: The authors declare that there are no conflicts of interest.