Johnsen, Stein Harald http://orcid.org/0000-0003-2382-1672
Jacobsen, Bjarne K.
Brækkan, Sigrid K.
Hansen, John-Bjarne
Mathiesen, Ellisiv B.
Article History
Received: 17 November 2017
Accepted: 14 May 2018
First Online: 25 May 2018
Ethics approval and consent to participate
: The Norwegian Data Inspectorate licensed all data. The Regional Committee for Research Ethics approved the study (REC no. 200005785–7/IAY/400). All the participants gave their written informed consent.
: All the participants gave their written informed consent for publication of the data.
: The authors declare that they have no competing interests.
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