Funding for this research was provided by:
Norges Forskningsråd (#213694, #223273)
Stiftelsen Kristian Gerhard Jebsen
The Liaison Committee for education, research and innovation in Central Norway
Text and Data Mining valid from 2019-03-05
Received: 7 May 2018
Accepted: 8 February 2019
First Online: 5 March 2019
Ethics approval and consent to participate
: The study was approved by the Norwegian Regional Committee for Medical and Health Research Ethics South East (2013/1236/REK South-East). Written informed consent was obtained from participants and/ or parents necessary due to age.
: The authors declare that they have no competing interests.
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