Article History
Received: 4 September 2019
Accepted: 13 January 2020
First Online: 8 February 2020
Ethics approval and consent to participate
: The Medical Ethics Committee of the University of Freiburg approved the study (EK37/19, date: March 19th 2019, PI: Axel Schmutz, MD). EK 37/19.
: Not applicable.
: The authors declare that they have no competing interests.