Funding for this research was provided by:
Received: 1 May 2020
Accepted: 22 October 2020
First Online: 30 November 2020
Ethics approval and consent to participate
: The study was approved from the Ethics Committee of University Witten/Herdecke. No consent to participate was necessary due to the retrospective nature of the study.
: Not applicable.
: The authors declare that they have no competing interests.