Funding for this research was provided by:
Text and Data Mining valid from 2018-09-29
Received: 12 May 2018
Accepted: 4 September 2018
First Online: 29 September 2018
Ethics approval and consent to participate
: The regional ethics committee waived the need for informed consent for the study with the reference number H-2-2012-53, and the study was approved by the Danish Data Protection Agency.
: Not applicable.
: The authors declare that they have no competing interests.
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