Funding for this research was provided by:
Received: 2 May 2017
Accepted: 12 January 2018
First Online: 26 January 2018
Ethics approval and consent to participate
: The study is in accordance with the Declaration of Helsinki and has been approved by the local ethics committee of the Medical Faculty of Mannheim, University of Heidelberg (ref# 2014-549 N-MA). The study was a retrospective analysis of a de-identified database and did not involve any new studies of human or animal subjects performed by any of the authors.
: Data were collected by chart review. The local ethics committee waived the necessity for individual informed consent.
: Roger Vogelmann, Sebastian Bischoff, Thomas Walter, Marlis Gerigk and Matthias Ebert declare that they have no conflict of interest.
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