Funding for this research was provided by:
Medical University of Gdansk
Text and Data Mining valid from 2019-02-01
First Online: 2 April 2019
Compliance with ethical standards
: The study was approved by the Ethics Committee of The Medical University of Gdańsk (NKBBN/406/2013) and followed the principles of the Declaration of Helsinki. From all the parents of juvenile participants, written informed consent was obtained.
: The authors declare that they have no conflict of interest.