Does Language Matter When Using a Graphical Method for Calculating the Speech Intelligibility Index?

Background: Graphical methods for calculating the speech intelligibility index (SII), such as the count-the-dot audiogram, are useful tools in quantifying how much weighted audibility is restored when amplification is used for individuals with hearing loss. The band-importance function (BIF), which is an important component of the SII, depends on the language. Thus, language may affect the prediction of weighted audibility using the graphical SII.

Purpose: The purpose of this study was to apply language-specific BIFs to develop and compare graphical SIIs for English, Korean, and Mandarin.

Research Design: The graphical SIIs were developed and compared using a research design that applied and analyzed existing datasets.

Data Collection and Analysis: Language-specific BIFs and dynamic ranges were used to derive graphical SIIs for English, Korean, and Mandarin. SII predictions were compared by calculating the language-specific predictions for the same audiometric configurations.

Results: The graphical SIIs for English, Korean, and Mandarin yielded different unaided and aided predictions for the same audiogram configurations.

Conclusions: A graphical SII helps patients easily understand their weighted audibility for unaided and aided conditions; thus, it is a useful counseling tool in the clinic. The most accurate graphical SII’s will, however, be based on a patient’s spoken language.

amplification - band-importance function - language - speech intelligibility index - weighted audibility