Background and objectives: This article is aimed at: 1.studying the relationship between Bone conduction pure tone thresholds and speech reception thresholds via bone conduction in normal patients 2.studying the stability and repeatability of the speech reception thresholds via bone conduction and 3. Comparing the characteristics of the function of the speech gain via bone conduction with that of air conduction.
Method: 60 normal hearing subjects (30 males and 30 females) were evaluated by air conduction pure tone audiometry, bone conduction pure tone audiometry and speech reception thresholds.
Results: Findings for the mentioned tests in all subjects were statistically insignificant. The results are prepared in tables and charts.
Conclusion: Pure tone thresholds and speech reception thresholds acquired by means of air conduction testing and bone conduction testing and the stability and repeatability were similar in both evaluations.

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: As clinical audiometry assessment of each ear needs to know interaural attenuation (IA), the aim of this study was to investigate Persian speech IA in adults.

Methods: This cross-sectional, analytic study was performed on 50 normal hearing students (25 males, 25 females), aged 18-25 years old in Faculty of Rehabilitation, Tehran University of Medical Sciences. Speech reception threshold (SRT) was determined with descending method with and without noise. Then speech IA for Persian spondaic words was caculated with TDH-39 earphones.

Results: Mean speech IA was 53.06±3.25 dB. There was no significant difference between mean IA in males (53.88±2.93 dB) and females (52.24±3.40 dB)(p>0.05). The lowest IA was in females (45 dB) and the highest IA was in males (60 dB). Mother's language has no significant effect on speech IA.

Conclusion: We may consider 45 dB as the lowest IA for Persian speech assessment, however generalization needs more study on a larger sample.