Funding for this research was provided by:
European Regional Development Fund
Text and Data Mining valid from 2019-05-10
Received: 4 December 2018
Accepted: 12 April 2019
First Online: 10 May 2019
Ethics approval and consent to participate
: The study was approved by the ethics committee at the Medical Faculty of the University of Leipzig and complies with the ethical standards of the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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