Received: 3 July 2017
Accepted: 1 May 2018
First Online: 21 May 2018
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of Urmia University of Medical Sciences. The purpose of this research was explained to all students and they were ensured that their responses would remain confidential. Written informed consents were obtained from all participants before inclusion in the study.
: The authors declare that they have no competing interests.
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