عنوان مقاله [English]
Background and Aims: The evaluation of probe microphone is the only gold standard to confirm the performance of hearing aids. In children, due to the fitting positive impact with real ear measurement on the children's communication skills and also considering that children are not able to express their hearing aid functional problems, the importance of the use of real ear measurement is felt more. Therefore, the present study was conducted to determine the difference between hearing aid output fitted by DSL prescriptive targets with approaches of real ear measurement and 2 cc coupler among 3-7 year-old hearing impaired children to understand the impact of earmold on these measurements.
Materials and Methods: In the present descriptive-analytical cross-sectional study, 3-7 year-old hearing impaired children with moderate to profound hearing losses were studied. For children’s assessment, after doing audiometerical tests, the children's hearing aids were planned in accordance with the DSL using relevant software formula, then hearing aids output was once measured using real ear measurement and once more using the 2 cc coupler. The obtained values were then compared.
Results: A significant difference was found between the sound pressure level average of target curve and that of hearing aids in the real ear measurement and 2 cc coupler in different intensity levels (p>0/05). The average difference betweeen sound pressure level of target curve and measured curve by real ear measurement compared with that of sound pressure level of target curve and measured curve by 2cc coupler was less than 10.
Conclusion: According to the findings of the present study, using real ear measurement in children seems a necessity. Also, the cause of the difference between the target and measure in real-ear measurement is the poor performance of various factors other than earmold (hearing aid, measurement, lack of correct prediction values in the settings application hearing aids, etc) and this issue is not related to the quality of the earmold.
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