Text and Data Mining valid from 2019-02-04
Received: 8 August 2018
Accepted: 28 January 2019
First Online: 4 February 2019
Ethics approval and consent to participate
: The project was approved by the faculty administration at each university and REC Central, the Regional Committees for Medical and Health Research Ethics, 7491 Trondheim, Norway (ref no.2013/2408). All participants received and signed an informed consent form prior to completing the questionnaire.
: Not applicable.
: The authors declare that they have no competing interests.
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