Translation into Spanish and validation of the Tinnitus Functional Index (TFI)

Objective

The objectives of this study were to translate into Spanish, cross-culturally adapt and validate the TFI.

Materials and Methods

The TFI questionnaire translated into Spanish (Sp-TFI) and cross-culturally adapted following the published guidelines on cross-cultural adaptation of health questionnaires was evaluated using two indicators. Its internal consistency was assessed with Cronbach’s α considering the Tinnitus Handicap Inventory (THI) as the gold standard. Further, its test-retest reliability was assessed with intraclass correlation coefficients (ICCs). ICCs were also calculated for the THI and visual analogue scales (VAS) for tinnitus tested and retested in all participants.

Results

The mean age of the 18 participants was 45.77 (SD: 11.87) years; 12 were female (66.67 %) and 6 were male (33.33%). Half of the participants experienced tinnitus in their left ear and half in their right. The mean pure-tone average (PTA) in the affected ear was 29.34 (SD: 8.08) dB-HL. Regarding internal consistency and reliability of the Sp-TFI respectively, Cronbach’s α was 0.83 and the ICC type (2,1) was 1 (CI: 0.99–1). Among the variables studied, we found the following independent predictors had statistically significant effects on THI score: sex (p < 0.01), PTA (p = 0.03), overall Sp-TFI score (p = 0.02) and Sp-TFI SL, R and A subscale scores (p = 0.03, p = 0.03, and p < 0.01, respectively).

Conclusion

Based on the internal consistency and reliability results obtained in this study, the cross-culturally adapted Spanish version of the TFI (Sp-TFI) has been validated for use in Spain.

Level of evidence

2B: Individual cohort study/low-quality randomized control studies