Received: 30 October 2017
Accepted: 1 June 2018
First Online: 8 June 2018
Ethics approval and consent to participate
: Research and Evaluation Committee of KETHEA granted permission for conducting the research. The study participants received a cover letter with information regarding the study aim, that participation was voluntary and that data would be treated confidentially. Hence, returning the questionnaire was interpreted as informed consent.
: The authors declare existence of no competing interests.
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