Funding for this research was provided by:
Norske Kvinners Sanitetsforening (Board decision dated 03.03.2015)
Samarbeidsorganet Helse Midt-Norge og NTNU (2015/128)
Received: 10 December 2018
Accepted: 4 July 2019
First Online: 16 July 2019
Ethics approval and consent to participate
: The Helsinki declaration was followed. The study was approved by the Regional Committee for Medical Research Ethics Central (reference number 2014/212). All participants signed an informed written consent before participation.
: Not applicable.
: The authors declare that they have no competing interests.