Article History
Received: 29 November 2017
Accepted: 21 November 2018
First Online: 30 November 2018
Ethics approval and consent to participate
: The study was approved by Research Ethics Review Committee (RERC) of Samara University dated 23 Dec 2016, and numbered ERC/0025/2016. A signed consent was taken from the study subjects before interview. Consent from a legal guardian was also acquired on behalf of underage participants.
: Not applicable.
: The authors declare that they have no competing interests.
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