Perception Versus Reaction: Comparison of Tinnitus Psychoacoustic Measures and Tinnitus Functional Index Scores

Purpose Psychoacoustic characteristics of tinnitus include its loudness and pitch. These characteristics are commonly measured and reported; however, it has not been shown that they are associated with the impact, or bothersomeness, of tinnitus. This study addressed this question by determining correlations between measures of tinnitus loudness, tinnitus pitch, and functional effects of tinnitus. Method Tinnitus loudness matches, pitch matches, a numeric rating scale (NRS) of tinnitus loudness, and responses to the 25-item tinnitus functional index (TFI) were obtained from 223 participants who experienced tinnitus for at least 6 months. Estimates of tinnitus pitch were calculated by use of a Bayesian sequential analysis technique. Results The total TFI score, as well as each of its 8 subscales, had weak or no correlations with both loudness matches and pitch matches, but moderate correlations with the NRS. Conclusions Psychoacoustic measurements used to estimate aspects of tinnitus perception appear unrelated to the impact of tinnitus, as assessed by a subjective outcome instrument. These psychoacoustic measurements do not assess reactions to tinnitus. These reactions should be measured by validated questionnaires, such as the TFI, which are designed to measure tinnitus impact. The moderate correlations between the NRS and the TFI suggest that self-reported tinnitus loudness is more a measure of tinnitus reactions than perception.