Funding for this research was provided by:
Śląski Uniwersytet Medyczny
Article History
Received: 15 March 2019
Accepted: 30 July 2019
First Online: 15 August 2019
Ethics approval and consent to participate
: We received permission for the implementation of our study from the Local Bioethics Committee of the Medical University of Silesia in Katowice (resolution number 29/2016 from 12/04/2016).
: Not applicable.
: The authors declare that they have no competing interests.