Received: 8 December 2020
Accepted: 16 February 2021
First Online: 1 March 2021
Ethics approval and consent to participate
: All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Ethics approval was granted by the Ethics Committee of the Heinrich-Heine-University of Düsseldorf and given the reference number 2019–632.
: Informed consent was obtained from all individual participants included in the study.
: The authors declare that they have no competing interests.