Text and Data Mining valid from 2019-01-30
Received: 2 July 2018
Accepted: 22 January 2019
First Online: 30 January 2019
Ethics approval and consent to participate
: The study conforms to the principles outlined in the declaration of Helsinki and was approved by the institutional review board (Ethics Committee of the Medical Faculty of the University Duisburg-Essen), protocol no.: 14–5775-BO. Due to the ethics approval, a patients’ informed consent has not been obtained.
: Not applicable.
: All authors have read and approved the manuscript and are aware of the submission. The authors declare no conflict of interest.
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