Received: 4 September 2019
Accepted: 30 March 2020
First Online: 25 May 2020
Ethics approval and consent to participate
: The study protocol was approved by the Health Ethics Committee of Hospital de São João, the National Committee on Data Protection and the Ministry of Education, and it meets the ethical requirements of the Helsinki Declaration. Parental approval of children’s participation was mandatory, and all data were gathered anonymously. Written informed consent was obtained from all individual participants included in the study. For further information, see [CitationRef removed].
: Not applicable.
: The authors declare that they have no competing interests.