Funding for this research was provided by:
Śląski Uniwersytet Medyczny (KNW-2-38/D/7/N, KNW-2-37/D/7/N)
Received: 31 January 2020
Accepted: 19 June 2020
First Online: 2 July 2020
Ethics approval and consent to participate
: The study protocol was approved by Bioethics Committee of the Medical University of Silesia -KNR/0022/KB1/82/II/15/16.
: Not applicable.
: The authors declare that there is no conflict of interest regarding the publication of this article.