Funding for this research was provided by:
Ruhr-Universität Bochum (5x5000)
Received: 10 July 2018
Accepted: 20 November 2018
First Online: 4 December 2018
Ethics approval and consent to participate
: According to our local ethics committee’s guidelines, a formal application was not necessary for our study, but the collection of demographic data was not permitted.
: Not applicable
: The authors declare that they have no competing interests.
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