Funding for this research was provided by:
German Federal Ministry of Education and Research (01GY1133)
Received: 21 January 2020
Accepted: 13 January 2021
First Online: 26 January 2021
Ethics approval and consent to participate
: The study conformed with the Declaration of Helsinki, written informed consent was obtained from all participants. The DiaDec-study was approved by the ethics committee of Heinrich Heine University Düsseldorf (study reference number 3762).
: Not applicable.
: The authors SOB, NC, BH, UL, SA, RS, OR and AI declare that they have no conflict of interest.