Helwa, Reham
Gansmo, Liv B.
Romundstad, Pål
Hveem, Kristian
Vatten, Lars
Ryan, Bríd M.
Harris, Curtis C.
Lønning, Per E.
Knappskog, Stian
Article History
Received: 25 May 2016
Accepted: 22 August 2016
First Online: 14 September 2016
Competing interests
: The authors declare no competing financial interests.