Text and Data Mining valid from 2018-08-02
Received: 28 January 2018
Accepted: 25 July 2018
First Online: 2 August 2018
Ethics approval and consent to participate
: The Ethics Committee at University Medical Centre Goettingen waived the need.for written informed consent from the participants for this retrospective study and approved the study (Registration no. 24/7/15AN). This study also conformed to the Helsinki Declaration (2013) and local legislation.
: Not applicable.
: The authors declare that they have no competing interests.
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