Text and Data Mining valid from 2019-05-02
Received: 1 December 2018
Accepted: 11 April 2019
First Online: 2 May 2019
Ethics approval and consent to participate
: The study was approved by the Regional Committee for Medical Research Ethics, South-East Norway (REK2014/2223). All participants provided written informed consent and, for former patients under 16 years old, parental consent.
: Not applicable
: The author declares that he has no competing interests.
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