Text and Data Mining valid from 2018-05-16
Received: 13 July 2016
Accepted: 30 April 2018
First Online: 16 May 2018
Ethics approval and consent to participate
: The protocol of the study was approved by the Local Bioethics Committee at Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun (decision no. KB 239/2011), and written informed consent was sought from all the study participants.
: The authors declare that they have no competing interests.
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