Received: 4 July 2019
Accepted: 14 October 2019
First Online: 19 December 2019
Ethics approval and consent to participate
: All participants signed an informed written consent after ensuring them about the confidentiality of the data obtained. All participants had the right to withdraw from the research at any time without giving reasons and without any negative consequences. The Research Ethics Committee at the Faculty of Medicine, Ain Shams University (FWA 00006444) approved the study, FMASU 448/2009.
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: The authors declare that they have no competing interests.