Article History
Received: 13 November 2017
Revised: 2 January 2018
Accepted: 15 February 2018
First Online: 28 February 2018
Compliance with ethical standards
:
: Author Jitka Veldema declares that she has no conflict of interest. Author Kathrin Bösl declares that she has no conflict of interest. Author Dennis Alexander Nowak declares that he has no conflict of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all individual participants included in the study.