Funding for this research was provided by:
Received: 16 March 2021
Accepted: 2 June 2021
First Online: 10 June 2021
: This is a purely observational study. The Research Ethics Committee of the University Hospital Regensburg has confirmed that no approval is required. The study was performed in accordance with the ethical standards in the 1964 Declaration of Helsinki. No administrative permission was required to access the analysed dataset. The data was anonymised before it use.
: Not applicable.
: The authors declare that they have no competing interests.