Sandvei, Marie Søfteland
Vatten, Lars J.
Bjelland, Elisabeth Krefting
Eskild, Anne
Hofvind, Solveig
Ursin, Giske
Opdahl, Signe
Article History
Received: 30 October 2017
Accepted: 27 July 2018
First Online: 6 August 2018
Compliance with ethical standards
:
: All authors declares that they have no conflicts of interest.