Received: 19 December 2017
Accepted: 20 March 2018
First Online: 3 April 2018
Ethics approval and consent to participate
: Informed consent was obtained from all individual participants included in the study. The Ethics Committee of the Medical University of Graz approved the conductance of this study (EK-Number: 29-373 ex 16/17).
: Not applicable.
: The authors declare that they have no competing interests.
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