Article History
Received: 27 August 2019
Accepted: 22 January 2020
First Online: 6 February 2020
Compliance with ethical standards
:
: All authors declare that they have no conflict of interest.
: Students interviewed in the surveys performed by the Brazilian Institute for Geography and Statistics (IBGE) were presented and signed informed consent to previous to participation in the study, and the surveys were approved by the National Committee of Ethics in Research (CONEP), opinion nos. 16805/2012 and 1006467/2015.
: Informed consent was presented to students interviewed in the surveys by the Brazilian Institute for Geography and Statistics (opinion nos. 16805/2012 and 1006467/2015) and data without individual identification was made publicly available (ExternalRef removed) for research purposes without requirement for further informed consent. Regarding authors participating in the coauthorship of the manuscript, all authors read and agreed with the final version of the manuscript.