An Explanatory Research on the Development of the Speech Test Signal in Hearing-Aid Fitting

Objective: International Speech Test Signal is developed with voices in 6 different languages and used for the determination of output frequencies of hearing aids in the real-ear measurement. This study aims to standardize the International Speech Test Signal for Turkish. Methods: The International Speech Test Signal passage was translated into Turkish; the resulting signal was arranged based on fundamental frequency, age, and gender characteristics, following the way the original signal was created. Patients with hearing loss were included. Following audiological tests, Real-Ear Aided Gain measurement was performed with the original International Speech Test Signal in the first step. The second step of the Real-Ear Aided Gain measurement was performed using International Speech Test Signal in Turkish. The gain values from both steps were compared statistically. Results: Evaluation of the signal as a whole indicates that the inclusion of the Turkish signal does not cause any difference in terms of amplitude distribution. Real-aided gain data obtained from the original International Speech Test Signal were compared with that of the Turkish-added International Speech Test Signal. Conclusion: Turkish can be added to the International Speech Test Signal that enables a more accurate fitting of hearing aids through the feedback of patients. Keywords: Hearing aids, International Speech Test Signal, sensorineural hearing loss, REM signal, hearing aids fitting