Received: 15 December 2018
Accepted: 26 March 2019
First Online: 8 April 2019
Ethics approval and consent to participate
: The design of this study was approved by the institutional ethics committee of the Research Institute for Endocrine Sciences, affiliated to the Shahid Beheshti University of Medical Sciences, and written informed consent was obtained from participants’ parents.
: Not applicable
: The authors declare that they have no competing interests.
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