Adaptation of the Tinnitus Handicap Inventory into Polish and its testing on a clinical population of tinnitus sufferers

<i>Objective</i>: To describe how the Tinnitus Handicap Inventory (THI) was translated into Polish (THI-POL) and to present psychometric data on how well it performed in a clinical population of tinnitus sufferers. <i>Design</i>: The original version of THI was adapted into Polish. The reliability of THI-POL was investigated using test–retest, Cronbach’s alpha, endorsement rate and item–total correlation. Construct validity and convergent validity were also assessed based on confirmatory factor analysis, inter-item correlation and Pearson product-moment correlations using subscale A (Tinnitus) of the Tinnitus and Hearing Survey (THS-POL); divergent validity was checked using subscale B (Hearing) of THS-POL. <i>Study sample</i>: A group of 167 adults filled in THI-POL twice over their three-day hospitalisation period. <i>Results</i>: Test–retest reliability for the total THI-POL scores was strong (<i>r</i> = 0.91). Cronbach’s alpha coefficient for the total score was high (<i>r</i> = 0.95), confirming the questionnaire’s stability. Confirmatory factor analysis (CFA) and inter-item correlation did not confirm the three-factor model. Convergent validity from the Tinnitus subscale of THS showed a positive strong (<i>r</i> = 0.75) correlation. Divergent validity showed only a moderate correlation. All analyses were statistically significant (<i>p</i> &lt; 0.01). <i>Conclusions</i>: THI-POL is a valid and reliable self-administered tool, which allows the overall tinnitus handicap of Polish-speaking patients to be effectively assessed.