Funding for this research was provided by:
Text and Data Mining valid from 2019-02-26
Received: 2 August 2018
Accepted: 21 February 2019
First Online: 26 February 2019
Ethics approval and consent to participate
: The study protocol was approved by the local ethical review board (EPN 2014/876–31/4).
: Not applicable.
: The authors declare that they have no competing interests.
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