Text and Data Mining valid from 2019-11-01
First Online: 20 November 2019
Compliance with Ethical Standards
: This research was submitted and approved by the Ethics Committee on Research involving Human Beings from Universidade Estadual de Londrina, Brazil, under the certificate number (CAAE) 5315 3515.6.0000.5231.
: The authors declare that they have no conflict of interest.
: The informed consent form was sent to parents or guardians, informing them about the study and requesting permission for their children’s participation