Received: 21 July 2019
Accepted: 30 July 2019
First Online: 19 September 2019
Ethics approval and consent to participate
: The study was conducted in accordance with the ethical principles of the 1975 Declaration of Helsinki, and it was reviewed and approved by Research Ethics Committee of Faculty of Medicine, Ain Shams University Institutional Review Board. A written informed consent was obtained from all the participants after explaining the aim and concerns of the study.
: Not applicable.
: The authors declare that they have no competing interests.