Funding for this research was provided by:
Universitetet i Oslo
Received: 28 August 2017
Accepted: 14 January 2019
First Online: 25 January 2019
Ethics approval and consent to participate
: The study was approved by the Regional Committee for Ethics in Medical Research in Norway (REK 2011/2498) on 28 February 2012, and by the Data Protection Authorities. All procedures performed in this study were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Patients were enrolled based either on written consent or on presumed consent in combination with written assent from the nearest relative.
: Not applicable
: The authors declare that they have no conflicts of interest.
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