Funding for this research was provided by:
Ministry of Health Republic of Kazakhstan (49017)
Received: 20 August 2019
Accepted: 30 October 2019
First Online: 14 November 2019
Ethics approval and consent to participate
: Informed consent to participate in the study was obtained from all participants in the study in accordance with the Protocol of the Ethical Committee of the Medical University of Semey and the requirements of the World Medical Association of Helsinki Declaration.
: Not applicable.
: The authors declare that they have no competing interests.