Safi, Ali-Farid
Grochau, Kathrin
Drebber, Uta
Schick, Volker
Thiele, Oliver
Backhaus, Tim
Nickenig, Hans-Joachim
Zöller, Joachim E.
Kreppel, Matthias
Article History
Received: 11 September 2018
Accepted: 11 January 2019
First Online: 23 January 2019
Compliance with ethical standards
:
: The authors declare that they have no conflicts of interest.
: Due to the retrospective nature of this study, it was granted an exemption in writing by the University Hospital of Cologne IRB. Our investigation followed the guidelines of the Helsinki Declaration. This article does not contain any studies with human participants or animals performed by any of the authors.
: For this type of study, formal consent is not required.