Method and Materials: This cross - sectional survey is carried out in pediatric clinic department of audiology faculty of rehabilitation, TMSU, on spring 1998. 102 top grade ranking children with normal hearing threshold

Results:1- The thresholds were not significantly different at any frequency (P>0.05) in test re-test trials.
2- The test minus re-test threshold for individual ears showed clinically reliable and acceptable range 0-10dB SPL for at least
99.74% of the ears at all frequencies.
3- The threshold differences between right & left cars in two test sessions were not significantly different (P>0.05) except for 14KHz.
4- High- frequency threshold in two test sessions showed no significant difference between girls & boys at all frequencies (P>0.05) (except for 16 & 20 KHz in right ear and 10 KHz in left ear).
Conclusion: This test can be used for evaluation of individual high-frequency threshold in all frequency as test re-tests tria1. Moreover, this test may use as a beneficial tool for monitoring different endogenous and exogenous auditory pathologies.
Consideration: it is found that this research is valid only among situation of this project. Any generalization needs further research.

Method & Material: This study examined the speech in noise test in 60 school age children with otitis media with effusion and 30 school age children with normal hearing in +5, 0 and -5 dB signal to noise ratio. The mean of age was 8.05 in study group and 8.25 in control group. Speech in noise test were performed for study group and control group in quiet an in noise. Speech noise presented ipsilaterally in both groups.Finding: The correlation of mean of SDS in +5, 0 and -5 dB signal to noise ratio between study group and control group, is significant.

Background and Aim: High frequency audiometry (HFA) provides a valuable tool and optimal index for distinguishing and monitoring many pathologies of the ear. The purpose of this study was to measure the reliability of HFA threshold in children.
Materials and Methods : In this cross-sectional study , 100 normal-hearing children, of 7 to 13 years old, including 50 boys and 50 girls were examined with a Belton 2000 audiometer and Sennheiser HD 250 earphones in Pediatric Clinic  of Audiology Department, Faculty of Rehabilitation of Tehran University of Medical Sciences.
Results: The threshold differences between right and left ears in two test sessions, were not significantly different except for 14 KHz. HFA threshold in two test sessions showed no significant difference in all frequencies between girls and boys but 16 and 20 KHz in right ear and 10 KHz in left ear.
Conclusion : The test-retest thresholds for iudividual ears showed ±0-10 dB SPL for difference at least  in 99.74 % of ears at all frequencies that is clinically reliable and acceptable.