Schüler-Toprak, Susanne
Weber, Florian
Skrzypczak, Maciej
Ortmann, Olaf
Treeck, Oliver
Article History
Received: 5 July 2018
Accepted: 3 October 2018
First Online: 16 October 2018
Ethics approval and consent to participate
: The institutional review board “Ethikkommission der Universität Regensburg” approved the retrospective study.
: Not applicable
: The authors declare that they have no competing interests.
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