1976 Volume 19 Issue 3 Pages 213-228
The study was carried out in patients with gradual slope sensorineural hearing losses and those with conduction losses.
The application of hearing aids was evaluated by performing speech discrimination test using both distorted speech and non-distorted speech, assessment of confusion matrix and a test for the easiness of hearing speech under different noise levels.
The results obtained from the present study demonstrated that in the test for application of hearing aids, there were a few patients who showed a slight improvement in discrimination when tested with distorted speech, while a remarkable improvement was seen in discrimination when tested with non-distorted speech, and that in the test for easiness of hearing speech, difference was observed between the scores in quiet and those in noise when using hearing aids either with open canal earmold or with occluding earmold.
From the above, it may be concluded that in order to perform adequate application test for hearing aids a test with distorted speech must be carried out in addition to that with standard speech.
Moreover, it seems necessary to develop hearing aids in which frequency response can be altered according to the environmental noise levels