Received: 26 October 2017
Accepted: 15 January 2018
First Online: 22 January 2018
Ethics approval and consent to participate
: Approval was gained from the Semmelweis University Regional and Institutional Committee of Science and Research Ethics, reference number: SE TUKEB 6/2015. Participants in our study provided informed consent to participate anonymously.
: Not applicable.
: The authors declare that they have no competing interests.
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