Funding for this research was provided by:
Liaison Committee for education, research and innovation in Central Norway (90061500)
Received: 1 November 2019
Accepted: 13 February 2020
First Online: 11 March 2020
Ethics approval and consent to participate
: This study was approved by the Regional Committee for Medical and Health Research Ethics of South-East Norway (reference number 2016/672) on date 04.27.2016. All partakers in the HUNT study signed a written informed consent form allowing the use of their data and samples for research purposes. Participants can request to withdraw their data from the HUNT database at any given moment.
: Not applicable.
: The authors declare that they have no competing interests.