Funding for this research was provided by:
Received: 14 December 2017
Accepted: 1 March 2018
First Online: 7 March 2018
Ethics approval and consent to participate
: We declare that the study has been performed in accordance with the Declaration of Helsinki and has been approved by the ethical Committee of the University of Würzburg (Ethical Committee Approval: Nr: 55/15 Date 1st Februar 2015).Written informed consent to participate in the study was obtained from each participant.
: Not applicable
: The authors declare that they have no competing interests.
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