Received: 17 June 2020
Accepted: 21 July 2020
First Online: 6 August 2020
Ethics approval and consent to participate
: The study was approved by the Regional Committee for Ethics in Medical Research (2014/644/REK sør-øst), and the HUNT Study was in addition approved by the Norwegian Data Inspectorate.
: Not applicable.
: The authors declare that they have no conflicts of interest.