Funding for this research was provided by:
Norges Forskningsråd (229092)
Received: 9 March 2018
Accepted: 11 December 2018
First Online: 5 January 2019
Ethics approval and consent to participate
: The study was approved and need for patient consent waived by the Regional Ethics Committee South-East, Norway (REC number: 2013/1321–1); and the Norwegian Data Inspectorate.
: Not applicable. No identifying patient data was used in the manuscript.
: The authors declare that they have no competing interests.
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