Funding for this research was provided by:
Received: 27 January 2021
Accepted: 21 February 2021
First Online: 4 March 2021
Ethics approval and consent to participate
: The study was reviewed and approved by the local Institutional Review Board (IRB) of the Ludwig-Maximilian-University Munich (approval number 703/16), and a waiver of consent was issued by the IRB.
: Not applicable.
: The authors declare that they have no competing interests.