Funding for this research was provided by:
The Research Council of Norway (187928, 201534, 227022/H20)
Article History
Received: 16 May 2018
Accepted: 27 December 2018
First Online: 16 January 2019
Ethics approval and consent to participate
: Participants gave informed written consent before participation. The Regional Committee for Medical and Health Research Ethics for South Eastern Norway approved the study protocol.
: Not applicable.
: The author declares that they have no competing interests.
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