Text and Data Mining valid from 2019-10-19
Received: 15 July 2019
Accepted: 9 October 2019
First Online: 19 October 2019
Ethics approval and consent to participate
: This study was approved by the institutional review board by the Ethics Committee of the Pomeranian Medical University in Szczecin and conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from each participant.
: Not applicable.
: The authors declare that they have no competing interests.