Text and Data Mining valid from 2019-04-04
Received: 16 October 2018
Accepted: 27 March 2019
First Online: 4 April 2019
Ethics approval and consent to participate
: The study was approved by the Ethics Committee, Klinikum rechts der Isar, Technische Universität München, which operates according to the Declaration of Helsinki. Written consent was waived by the institutional review board because of the retrospective study design (ethics approval reference number 108/17 S).
: Not applicable.
: The authors declare that they have no competing interests.
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