Ethical considerations
Informed consent was obtained from participants and they were advised
that they can leave the study at any time point and this will not hinder
their current treatment or future visits to the hospital and the quality
of care they would receive. This study was conducted in accordance with
the 1964 Helsinki Declaration and approved by the Tehran University of
Medical Sciences ethics board committee (Ethics code:
IR.TUMS.VCR.REC.1399.076).