Article History
Received: 13 May 2017
Accepted: 20 November 2017
First Online: 29 November 2017
Compliance with ethical standards
:
: Author Ulrich Ansorge declares that he has no conflict of interest. Author Davood Gozli declares that he has no conflict of interest. Author Florian Goller declares that he has no conflict of interest.
: All procedures performed were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments.
: Informed consent was obtained from all individual participants included in the study.