Measuring tinnitus loudness using constrained psychophysical scaling.

PURPOSE We measured tinnitus loudness using a new method of psychophysical scaling with the aim of introducing a potentially useful new procedure to the literature. METHOD Fourteen adults reporting tinnitus were trained to use a standardized loudness scale, and then they used that response scale to assess loudness of nonstandard stimuli and of their tinnitus. We also measured tinnitus loudness and pitch using a computer-based matching procedure, and we measured the impact of tinnitus on daily living using the Tinnitus Handicap Inventory (THI; C. W. Newman, G. P. Jacobson, & J. B. Spitzer, 1996) for those 14 individuals and an additional 2 participants. Results and Conclusions Our 14 trained participants judged loudness similarly to normal hearing participants for pure tones at normal hearing, nontinnitus frequencies-implying that their judgments of tinnitus loudness were valid. Constrained scaling of tinnitus loudness yielded measurements that were substantially greater than the sensation level of sounds matched to tinnitus loudness. Our total of 16 participants fell into 2 groups on the basis of hearing loss, extent of abnormal loudness growth at the tinnitus frequency, and several aspects of tinnitus experience. Finally, as previously found, there was little correlation between tinnitus loudness, no matter how measured, and the impact of tinnitus on daily life as measured by the THI.