Funding for this research was provided by:
Universität zu Köln
Received: 5 December 2019
Accepted: 13 August 2020
First Online: 21 August 2020
Compliance with Ethical Standards
: The authors declare that they have no conflict of interest.
: All procedures performed in this study that involve human participants were in accordance with the ethical standards of the institutional research committee (Ethik-Kommission der Medizinischen Fakultät der Universität zu Köln, reference number: 17–169) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study.