Received: 29 November 2019
Accepted: 25 February 2020
First Online: 14 April 2020
Ethics approval and consent to participate
: All participants signed a written informed consent and the study was approved by Tehran University of Medical Sciences ethics committee (IR.TUMS.VCR.REC.1395.1597).
: Not applicable.
: All of authors declared that they have no competing interests.