Funding for this research was provided by:
Norges Forskningsråd (238042)
Text and Data Mining valid from 2019-05-07
Received: 19 December 2018
Accepted: 10 April 2019
First Online: 7 May 2019
Ethics approval and consent to participate
: NPR, KUHR and NorPD were analyzed with anonymized patient IDs, and were not linked. The study was approved by the Norwegian Center for Research Data (project reference 52580).
: No details on individuals are reported within the manuscript.
: The authors have no competing interests.
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