Received: 16 April 2019
Accepted: 13 October 2019
First Online: 1 November 2019
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study was approved by the Ethics Committee for Scientific Research of LUMSA University of Rome, Italy.
: We obtained a consent to participate from any parent.
: The authors declare that they have no competing interests.