Received: 22 December 2019
Accepted: 14 February 2020
First Online: 30 March 2020
Ethics approval and consent to participate
: The approval for this study was obtained by the local ethics committee “Faculty of Medicine, Christian-Albrechts-University in Kiel” in Germany (D417/17). Informed written consent to participate in the study was provided by all participants at the admission.
: Not applicable.
: The authors declare that they have no competing interests.