Funding for this research was provided by:
Berta Ottenstein Programme, Faculty of Medicine, University of Freiburg
Article History
Received: 14 August 2018
Accepted: 25 October 2018
First Online: 8 November 2018
Ethics approval and consent to participate
: This study was approved by the ethics committee of the University of Freiburg (vote Nr. 461/17).
: Not applicable.
: The authors declare that they have no competing interests.
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