Elewa, Mohamed Khaled
Article History
Received: 9 September 2017
Accepted: 25 October 2018
First Online: 7 November 2018
Ethics approval and consent to participate
: The study was approved by Ain Shams University Faculty of Medicine Ethical Committee on October 8, 2016. The study was retrospective, so consent to participate was not required.
: Not applicable
: The author declares that he has no competing interests.
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