Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (SU 222/6-1)
Received: 17 December 2018
Accepted: 20 May 2020
First Online: 29 May 2020
Ethics approval and consent to participate
: This research was approved by the ethics committee of the Medical School of the University of Leipzig. All participants gave their written consent to participate in the study and received financial compensation.
: Not applicable.
: The authors declare that they have no competing interests.