Eide, Per Kristian http://orcid.org/0000-0001-6881-9280
Vatnehol, Svein Are Sirirud http://orcid.org/0000-0002-7900-0534
Emblem, Kyrre Eeg
Ringstad, Geir
Article History
Received: 25 October 2017
Accepted: 26 April 2018
First Online: 8 May 2018
Competing Interests
: The authors declare no competing interests.