Text and Data Mining valid from 2018-03-20
Received: 31 July 2017
Accepted: 26 February 2018
First Online: 20 March 2018
Ethics approval and consent to participate
: Approved by the medical ethics committee of the Faculty of Medicine in Mannheim, University of Heidelberg, Germany. As this was a retrospective study, the ethics committee waivered the need for informed consent.
: As this was a retrospective study, consent from included patients was not required.
: The authors declare that they have no competing interests.
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