Text and Data Mining valid from 2018-10-29
Received: 2 July 2018
Accepted: 24 October 2018
First Online: 29 October 2018
Compliance with ethical standards
: The study protocol was approved by the Internal Review Board at the Poznan University of Medical Sciences. Written informed consent was obtained from all study participants.
: Not applicable.
: The datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.
: The authors have declared that no competing interests exist.