Cross-cultural adaptation and psychometric validation of the Kannada version of the Extended Effort Assessment Scale (EEAS-K) in adults with hearing loss

Introduction: The Extended Effort Assessment Scale (EEAS) is a recently developed questionnaire for measuring listening effort, but a validated version for Kannada speakers is lacking. This study aimed to translate, culturally adapt, and psychometrically validate the EEAS for the Kannada-speaking adults with hearing loss. Method: The EEAS was translated into Kannada (EEAS-K) following rigorous forward and back translation, expert committee review and cognitive debriefing. The final EEAS-K was then field-tested with 100 native Kannada-speaking adults with hearing loss (predominantly non-hearing aid users, 92%). Psychometric validation included assessing construct validity via exploratory factor analysis, Rasch analysis using item response theory (IRT), internal consistency (Cronbach’s alpha), convergent validity via a Visual Analogue Scale (VAS), test-retest reliability with an Intraclass correlation coefficient (ICC) and Differential Item Functioning (DIF). Results: All 10 EEAS-K items demonstrated acceptable content validity (CVR = 1.00). EFA, guided by eigenvalues and the scree plot, provided initial support for a unidimensional structure, with a single factor accounting for 32.7% of the variance. Rasch analysis supported essential unidimensionality (first residual eigenvalue = 1.90). Nine of 10 items showed acceptable infit MNSQ values (0.64–1.34); Q8 (telephone) showed elevated infit (1.92) and outfit (1.83) values, indicating misfit, which may reflect the unique and multidimensional cognitive demands of technology-mediated communication in this population. Person-item targeting remained within acceptable clinical limits, though items were slightly easier for the average person’s ability (person mean = 0.49 logits). The EEAS-K demonstrated excellent internal consistency (α = 0.886), moderate to strong convergent validity with the VAS (r = 0.611), and excellent test-reliability (ICC = 0.91). DIF analysis identified significant gender-based DIF for Q7 and age-based DIF for Q7 and Q8, suggesting raw scores for these specific items should be interpreted with caution across these demographics. No significant DIF was found for hearing-loss-severity. Conclusion: The EEAS-K is a reliable and valid tool for assessing listening effort in Kannada-speaking adults with hearing loss. The Wright map demonstrates adequate person-item targeting, and the dual-method psychometric approach provides satisfactory measurement evidence supporting clinical and research use.