Kalanxhi, Erta
Meltzer, Sebastian
Schou, Jakob Vasehus
Larsen, Finn Ole
Dueland, Svein
Flatmark, Kjersti
Jensen, Benny Vittrup
Hole, Knut Håkon
Seierstad, Therese
Redalen, Kathrine Røe
Nielsen, Dorte Lisbet
Ree, Anne Hansen
Article History
Received: 26 December 2017
Revised: 20 March 2018
Accepted: 22 March 2018
First Online: 26 April 2018
Competing interests
: The authors declare no competing interests.
: The study protocols were approved by the Regional Committee for Medical and Health Research Ethics of South Norway (REK-S-05059) and Committees for Research Ethics of the Capital Region of Denmark (H-C-2008-0001 and H-A-2009-019). The studies were performed in accordance with the Declaration of Helsinki. Written informed consent was required for participation.