Received: 9 October 2018
Accepted: 5 February 2019
First Online: 21 February 2019
Ethics approval and consent to participate
: The aim and procedures of the study were explained to every participant and an informed consent was obtained before being enrolled in the study. The study was approved by the ethical committee of the Faculty of Medicine, Cairo University has allowed this study. Date of approval on 15th August 2017 and final approval of whole work on 17th of July 2018, but the reference number of approval is not available.
: Not applicable.
: The authors declare that they have no competing interests. We declare that the research was conducted in the absence of any commercial relationships that could be constructed as a potential conflict of interest.
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