Article History
Received: 11 October 2019
Accepted: 6 February 2020
First Online: 6 April 2020
Ethics approval and consent to participate
: The authors assert that all procedures contributing to this work comply with the ethical standards of the relevant national guides on the care and has been approved by the ethical committee in Al-Azhar University, Cairo, Egypt (reference number is not available). Parental consents were obtained verbally.
: Not applicable.
: The authors declare that they have no competing interests.