Article History
Received: 14 October 2018
Accepted: 8 May 2019
First Online: 16 May 2019
Ethics approval and consent to participate
: This cross-sectional study was conducted as anonymous questionnaire, which is the reason why an ethics approval was not necessary according to the “Ethics Committee of the city of Vienna” (Thomas-Klestil-Platz 8, 1030 Vienna, Austria, submission number: MA15-EK/17_162_VK_NZ). Participation was voluntary. All participants were explained the reasons and aims of this questionnaire and gave written consent by filling in the questionnaire.
: A direct consent for publication was not necessary as no individual data are presented.
: The authors declare that they have no competing interests.
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