Article History
First Online: 20 September 2019
Compliance with Ethical Standards
:
: Ana C. Almeida, M. Engrácia Leandro, and M. Graça Pereira declare that there is no conflict of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee of the two Portuguese hospitals (Process no. 68-CHLC) and with the 1964 Helsinki Declaration and its later amendments.
: All parents and adolescents signed an informed consent to participate in this study.