Text and Data Mining valid from 2018-08-06
Received: 18 January 2018
Accepted: 23 July 2018
First Online: 6 August 2018
Ethics approval and consent to participate
: The dataset observed in this study was private. The Danish Data Protection Authority (Datatilsynet) approved usage of the data (j.nr 2013–41-2568). The data analysed was de-identified.
: not applicable.
: The authors declare no conflict of interests.
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