Funding for this research was provided by:
Danmarks Frie Forskningsfond (8022-00243A)
Bundesministerium für Bildung und Forschung (16SV7657)
Received: 9 July 2019
Accepted: 29 October 2019
First Online: 14 November 2019
Ethics approval and consent to participate
: This study was approved by the ethics committee of the Universitätsmedizin Göttingen (approval number: 22/04/16). Prior to their participation, participants received detailed information about the study and have given written and oral consent.
: Not applicable.
: The authors declare that they have no competing interests.