Funding for this research was provided by:
The Sophies Minde Foundation
Received: 23 January 2019
Accepted: 28 March 2019
First Online: 8 April 2019
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 (the children themselves if aged ≥16 years and the parents/guardians of children aged < 16 years together with the children’s assent).
: Not applicable.
: The authors declare that they have no competing interests.
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