Received: 31 October 2018
Accepted: 20 December 2018
First Online: 18 January 2019
Ethics approval and consent to participate
: This study was approved by Cairo University Clinical Research Ethics Committee, and informed verbal consents were obtained from parents of the included children. Informed verbal consent has been obtained because most of our patient guardian’s are uncomfortable with reading and writing and may be too embarrassed by the written consent process to participate in a research. This informed verbal consent has been approved by Cairo University Clinical Research Ethics Committee as it cover the basic elements of the consent process that include full disclosure of the nature of the research, adequate comprehension on the part of the potential participant, and the participant`s voluntary choice to participate. The study design conformed to the Revised Helsinki Declaration of Bioethics.
: Not applicable
: The authors declare that they have no competing interests.
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