Funding for this research was provided by:
Helse Vest (911629)
Text and Data Mining valid from 2018-05-30
Received: 4 February 2017
Accepted: 15 May 2018
First Online: 30 May 2018
Ethics approval and consent to participate
: The study was approved by the Regional Committee for Medical and Health Research Ethics of Western Norway (REK ref. number 2010/3310).
: The authors declare that they have no competing interests.
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