Funding for this research was provided by:
Fundação para a Ciência e a Tecnologia (PTDC/DTP-SAP/1520/2014)
Received: 17 October 2019
Accepted: 1 June 2020
First Online: 10 June 2020
Ethics approval and consent to participate
: Prior to commencing the study, the protocol was approved by Direção Geral do Ensino (Portuguese Ministry of Education) and Comissão Nacional de Proteção de Dados (CNPD), the Portuguese Data Protection Authority (Authorization number 745/2017). All procedures were in accordance with the 1964 Helsinki declaration and its later amendments. Written informed consent was obtained from children’s parents.
: Not applicable.
: Aristides M. Machado-Rodrigues is an Editorial Board Member. The remained authors have indicated they have no potential conflicts of interest to disclose and that they have no financial relationships relevant to this article to disclose.