Text and Data Mining valid from 2018-09-10
Received: 12 June 2018
Accepted: 31 August 2018
First Online: 10 September 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of the Medical University of Innsbruck (AN4757 315/4.4).
: Not applicable
: The authors declare that they have no competing interests.
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