Text and Data Mining valid from 2019-01-02
Received: 15 October 2018
Accepted: 26 December 2018
First Online: 2 January 2019
Compliance with ethical standards
: The authors declare that they have no conflict of interest.
: The local ethics committee approved the study (Agreement no. 1/WIM/2014).
: The individual informed consent was not required due to retrospective nature of the study.