Funding for this research was provided by:
Tomsk Polytechnic University (14.Z50.31.0029, 14.Z50.31.0029, 14.Z50.31.0029)
Received: 18 September 2018
Accepted: 24 January 2019
First Online: 11 February 2019
Ethics approval and consent to participate
: At the time the study was conducted, there was no ethics committee at the university. However, the study was conducted in accordance with the Helsinki declaration and its later amendments. All researchers and interviewers involved in the study adhered to the ethical standards of the Helsinki declaration. Informed consent was obtained from all individual participants prior to the interview. All respondents were informed that their participation was voluntary and anonymous, and that they could withdraw from the interview at any time.
: The manuscript does not contain any individual person’s data in any form.
: The authors declare that they have no competing interest.
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