Kirkøen, Benedicte
Berstad, Paula
Botteri, Edoardo
Åvitsland, Tone Lise
Ossum, Alvilde Maria
de Lange, Thomas
Hoff, Geir
Bernklev, Tomm
Article History
Received: 18 November 2015
Revised: 21 December 2015
Accepted: 11 January 2016
First Online: 11 February 2016
Competing interests
: The authors declare no conflict of interest.