Funding for this research was provided by:
Bundesministerium für Gesundheit (IIA5-2513FSB801)
Received: 21 November 2016
Accepted: 22 January 2018
First Online: 9 February 2018
: The authors declare that they have no competing interest.
: A positive ethics committee vote was obtained for the interview study from the ethics committee of the Albert-Ludwigs-University Freiburg (number 53/14). Informed consent was obtained in writing from all participants.
: Not applicable.
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