Received: 5 May 2020
Accepted: 20 October 2020
First Online: 23 October 2020
Ethics approval and consent to participate
: The study was approved by the Bioethics Committee of the Karol Marcinkowski Medical University, Poznan, Poland (no. 893/18). Furthermore, secondary school students had been given adequate information about the purpose of the study. Individual personal information was kept confidentially.
: Not applicable.
: The authors declare that there they have no conflicts of interest.