Funding for this research was provided by:
Śląski Uniwersytet Medyczny (KNW-1-086/K/7/K)
Text and Data Mining valid from 2018-09-14
Received: 7 January 2018
Accepted: 4 September 2018
First Online: 14 September 2018
Ethics approval and consent to participate
: This study was approved by the ethics committee of the Medical University of Silesia (ref. KNW/0022/KB1/134/15). Written informed consent was obtained from all participants in the study.
: Not applicable
: The authors declare that they have no competing interests.
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