Text and Data Mining valid from 2018-05-02
Received: 10 January 2018
Accepted: 23 April 2018
First Online: 2 May 2018
Ethics approval and consent to participate
: Not applicable. (Ethics approval was waived by the Ceav Ethical Committee. The study was conducted according to the guidelines of the institution of the first author and in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.) All the participants expressed their consent to participate to this study.
: The participants consented to the utilisation of their data for the purposes of this scientific study.
: The authors declare that they have no competing interests.
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