Funding for this research was provided by:
The Sophies Minde Foundation
Received: 30 April 2018
Accepted: 1 October 2018
First Online: 17 October 2018
Ethics approval and consent to participate
: The study was approved by the Norwegian South East Regional Ethics Committee for Medical Research (2014/188). All participants provided written informed consent/assent.
: Not applicable.
: The authors declare that they have no competing interests.
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