Funding for this research was provided by:
Helse Vest Regionalt Helseføretak
Text and Data Mining valid from 2019-04-03
Received: 4 January 2019
Accepted: 19 March 2019
First Online: 3 April 2019
Ethics approval and consent to participate
: The study protocol conformed to the ethical guidelines of the 1975 Declaration of Helsinki and was approved by the Regional Committees for Medical and Health Research Ethics, Norway (reference number: 2012/753).
: Not applicable.
: The authors declare that they have no competing interests.
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