Funding for this research was provided by:
Received: 17 January 2021
Accepted: 10 May 2021
First Online: 29 May 2021
: This study was conducted according to the recommendations of the World Medical Association (Declaration of Helsinki: [CitationRef removed]). Ethical approval has been granted by the independent Research Ethics Committee of the Medical Faculty of Friedrich-Alexander-University of Erlangen-Nuremberg (Re.-No. 4510). All study participants gave full informed written consent to participate in the study.
: Not applicable.
: The authors declare that there is no conflict of interest.