Article History
Received: 11 September 2017
Accepted: 22 February 2019
First Online: 19 March 2019
Ethics approval and consent to participate
: The study was cleared by the ethical committee of the Medical Faculty of Muenster University (2012-268-f-S). Participants were informed about the purpose of the study, the voluntary and anonymous nature of the data collection, and the analysis procedure. Written informed consent was obtained.
: Not applicable.
: The authors declare that they have no competing interests.
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