Funding for this research was provided by:
Aase og Ejnar Danielsens Fond
Text and Data Mining valid from 2018-10-16
Received: 27 March 2018
Accepted: 13 August 2018
First Online: 16 October 2018
Ethics approval and consent to participate
: Written informed consent was provided from the participants. The study was approved by the Regional Data Protection Agency (J.no. 1–16–02-86-16). Approval by the Regional Ethical Committee was not needed due to the study’s methodological nature. The letter of exemption from the Regional Ethical Committee is available from the author on request (case no. 86 / 2017).
: Not applicable
: The authors declare that they have no competing interests.
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