Modified Rhyme Test for Evaluating Turkish Speech Intelligibility
Abstract
Objective: There are both objective and subjective tests for evaluating the speech intelligibility. Speech Intelligibility Index (SII) and Modified Rhyme Test (MRT) are the most common methods for objective and subjective tests, respectively. While objective tests do not depend on the language, subjective tests are applied to the hearing-impaired subjects in their language. In these tests, hearing-impaired subjects try to recognize the sound by looking at the word lists in their hand. The word lists can be presented as two-word or six-word choices in design. However, the preferred type a is six-word choice for MRT. Up to now, these word lists were developed in different languages with different methods. For Turkish language, only two-word choice lists were developed; there was no study related to the Turkish language with six-word choice. In this study, we aimed to develop applicable six-word Turkish MRT lists by using hearing-impaired subjects.
Methods: In this study, three different six-word Turkish MRT lists were developed according to the phonetic characteristics of the Turkish language, and these lists were tested via 12 hearing-impaired subjects. In the lists, 5 different Turkish phonetic characteristics were taken into account. For the analysis, the detailed audiograms (18 octave band) of hearing-impaired subjects were used.
Results: Detailed statistical analysis for phonetic variations were shown for each hearing-impaired subject. Having correct structure and robust word choices for MRT lists were shown by comparing the equivalent speech spectrum levels of sounds and MRT results of the hearing-impaired subjects.
Conclusion: New Turkish MRT lists were developed according to the phonetic characteristics of the Turkish language. Usability of the lists was shown by audiological test with the hearing-impaired subjects. Statistical analysis and the results of tests showed that developed Turkish MRT lists can be used in audiological studies as a reference material.
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