Funding for this research was provided by:
Fundação para a Ciência e a Tecnologia (POCI-01-0145-FEDER-006862; Ref. UID/DTP/04750/2013, FCT PTDC/DTP-EPI/3306/2014, IF/01060/2015)
European Regional Development Fund (NORTE-01-0145-FEDER-000003)
UK Medical Research Council (MC_UU_12013/5)
UK National Institute of Health Research Senior Investigator (NF-SI-0611-10196)
Text and Data Mining valid from 2018-07-02
Received: 13 December 2017
Accepted: 20 June 2018
First Online: 2 July 2018
Ethics approval and consent to participate
: All the phases of the study complied with the Ethical Principles for Medical Research Involving Human Subjects expressed in the Declaration of Helsinki. The study was approved by the University of Porto Medical School/ Centro Hospitalar São João ethics committee and all parents or legal representative signed an informed consent according Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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