Text and Data Mining valid from 2018-07-28
Received: 15 April 2018
Accepted: 23 July 2018
First Online: 28 July 2018
Ethics approval and consent to participate
: The study was approved by the Tehran University of Medical Science. All research activities were performed in accordance with the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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