Received: 16 October 2020
Accepted: 19 November 2020
First Online: 9 December 2020
Ethics approval and consent to participate
: This study was approved by the Ethics Commission (135/14) of the Goethe University Frankfurt am Main. All participants signed, in advance, the required consent form for participation in the study.
: Not applicable.
: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.