Atılım Atılgan, Murat Erinç, Cansu Tosyalı Salman, M. Tayyar Kalcıoğlu
Journal of Academic Research in Medicine - 2026;16(1):17-23
Objective: The speech intelligibility index (SII) quantifies the proportion of speech that is audible to a listener. Its predictive accuracy is based on the acoustic and phonetic properties of the language it uses. Our study evaluated the feasibility of using the English-based SII for Turkish-speaking individuals with sensorineural hearing loss, comparing younger and older adults. Methods: In this retrospective cross-sectional study, 161 participants (68 younger adults and 93 older adults) with bilateral sensorineural hearing loss were included. Hearing thresholds, word recognition scores (WRS), and SII values were analyzed. Non-parametric statistical analyses, including the Wilcoxon signed-rank test for paired comparisons, Mann-Whitney U test for group differences, Spearman's rank correlation for associations, and Fisher Z-test with bootstrap analysis to compare correlation coefficients were conducted to evaluate differences and relationships among audiological measures. Results: Significant positive correlations were found between SII and WRS in both age groups (r=0.73 for younger adults; r=0.65-0.70 for older adults). Older adults had higher high-frequency thresholds and lower WRS (p<0.001), but no age-related differences were observed in SII or the pure-tone average. Conclusion: The English-based SII can be used as a provisional tool for Turkish speakers, but age-related and frequency-specific variations highlight the need for a language-specific model.
