Funding for this research was provided by:
OsloMet – Oslo Metropolitan University
Text and Data Mining valid from 2018-10-22
Received: 10 January 2018
Accepted: 10 October 2018
First Online: 22 October 2018
Ethics approval and consent to participate
: The project proposal has been approved by The Regional Committee for Medical Research Ethics in South East Norway (Ref. 2014/2051). Informed consent was obtained from all participants included in the analyses, and the project is conducted according to the WMA Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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