Funding for this research was provided by:
Received: 13 March 2019
Accepted: 25 July 2019
First Online: 5 August 2019
Ethics approval and consent to participate
: Approval was obtained from the Ethics and Research Committees of the School of Medicine of Tecnologico de Monterrey. All parents or legal guardians gave their written informed consent. The participants did not receive any form of compensation for participating in this study.
: Not applicable.
: The authors declare that they have no competing interests.