Bostel, Tilman
Nicolay, Nils Henrik
Welzel, Thomas
Bruckner, Thomas
Mattke, Matthias
Akbaba, Sati
Sprave, Tanja
Debus, Jürgen
Uhl, Matthias
Article History
Received: 24 April 2018
Accepted: 8 August 2018
First Online: 23 August 2018
Ethics approval and consent to participate
: The Heidelberg Ethics Committee approved this study on 7th August 2012 (S-165/2012). Due to the retrospective design, informed consent was not required.
: Not applicable.
: The authors declare that they have no competing interests.
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