Assessing Meaningful Improvement: Focus on the Tinnitus Functional Index.

Many studies have attempted to determine methodology for interpreting change on outcome instruments that result from an intervention. The objective of these studies has been to devise methods to identify the minimal level of change that would be consistent with actual benefit perceived by the patient, and not just statistically significant change. With respect to intervention for bothersome tinnitus, the authors of the original study to develop and validate the Tinnitus Functional Index (TFI) suggested that a minimum 13-point reduction in the TFI score was likely to reflect a change perceived as meaningful to an individual. The 13-point estimation of meaningful change for an individual is appropriate for use with any adult seeking care for tinnitus. However, it cannot be relied upon in isolation to determine if an individual believes that there has been a noticeable, or meaningful improvement in their quality of life. It is important to use subjective impressions elicited from the patient to assist in interpreting the meaning of TFI data for an individual. For clinicians engaging in care for tinnitus, we recommend using the TFI and pairing it with the patient's belief/impression as to whether they are doing better than they were before care for tinnitus was provided. Ideally, the outcome assessment would be conducted by someone other than the clinician who provided the intervention.

Audiologic characteristics in a sample of recently-separated military Veterans: The Noise Outcomes in Servicemembers Epidemiology Study (NOISE Study).

Military Service Members are often exposed to high levels of occupational noise, solvents, and other exposures that can be damaging to the auditory system. Little is known about hearing loss and how it progresses in Veterans following military service. This epidemiology study is designed to evaluate and monitor a cohort of Veterans for 20 years or more to determine how hearing loss changes over time and how those changes are related to noise exposure and other ototoxic exposures encountered during military service. Data reported here are from baseline assessments of the first 100 study participants (84 males; 16 females; mean age 33.5 years; SD 8.8; range 21-58). Each participant was asked to complete a comprehensive audiologic examination and self-report questionnaires regarding sociodemographic characteristics, noise and solvent exposures, health conditions common among post-deployment Veterans, and the social and emotional consequences of hearing loss. For this relatively young cohort, 29% exhibited hearing loss, defined as average hearing threshold >20 dB HL in the conventional audiometric range. Forty-two percent exhibited hearing loss in the extended-high-frequency audiometric range using the same criterion (average hearing threshold >20 dB HL). Certain factors were found to be associated with poorer hearing in both conventional and extended-high-frequency ranges, including age, type of military branch, years of military service, number of military deployments, noise exposure, tinnitus, and a positive screen for post-traumatic stress disorder. Although the majority of participants had hearing within normal limits, 27% reported a self-perceived mild/moderate hearing handicap and 14% reported a significant handicap. Further research is needed to identify a cause for this discrepancy in audiologic results versus self-report. The information obtained from this longitudinal study could be used in future resource planning with the goal of preventing, as much as possible, the development of hearing loss during military service, and the exacerbation of prevalent hearing loss after military service and over Veterans' lifetimes.

Assessment of tinnitus: measurement of treatment outcomes.

There is a wide range of assessment techniques for tinnitus, but no consensus has developed concerning how best to measure either the presenting features of tinnitus or the effects of tinnitus treatments. Standardization of reliable and valid tinnitus measures would provide many advantages including improving the uniformity of diagnostic and screening criteria between clinics and facilitating comparison of treatment outcomes obtained at different sites. This chapter attempts to clarify issues involved in developing self-report questionnaires for the assessment of tinnitus. While the tinnitus questionnaires that are currently available provide valuable information on which to base diagnostic and screening decisions, they were not originally developed in such a way as to maximize their sensitivity to treatment-related changes in tinnitus. As a result, their construct validity for measuring treatment benefit has not received appropriate attention. In this paper, special emphasis is devoted to the use of effect sizes as an estimate of the ability of questionnaires (and their individual items) to measure changes associated with treatment. We discuss the criteria relevant to evaluating the effectiveness of a questionnaire for diagnostic purposes vs. for treatment-evaluation purposes, and we present a detailed illustration of how the various criteria have been applied in a recent questionnaire development effort.

Clinical trial to compare tinnitus masking and tinnitus retraining therapy.

CONCLUSION: Both tinnitus masking (TM) and tinnitus retraining therapy (TRT) can be effective therapies for amelioration of tinnitus. TM may be more effective for patients in the short term, but with continued treatment TRT may produce the greatest effects. OBJECTIVES: Although TM and TRT have been used for many years, research has not documented definitively the efficacy of these methods. The present study was a controlled clinical trial to prospectively evaluate the clinical efficacy of these two methods for US military veterans with severe tinnitus. SUBJECTS AND METHODS: Over 800 veterans were screened to ensure that enrolled patients had tinnitus of sufficient severity to justify 18 months of individualized treatment. Qualifying patients (n=123) were placed quasi-randomly (alternating placement) into treatment with either TM or TRT. Treatment was administered at 0, 3, 6, 12, and 18 months. Outcomes of treatment were evaluated primarily using three self-administered tinnitus questionnaires (Tinnitus Handicap Inventory, Tinnitus Handicap Questionnaire, Tinnitus Severity Index). RESULTS: Findings are presented from the three written questionnaires with respect to three categories of patients: describing tinnitus as a 'moderate,' 'big,' and 'very big' problem at baseline. Based on effect sizes, both groups showed considerable improvement overall. In general, TM effects remained fairly constant over time while TRT effects improved incrementally. For the patients with a 'moderate' and 'big' problem, TM provided the greatest benefit at 3 and 6 months; benefit to these TRT patients was slightly greater at 12 months, and much greater at 18 months. For patients with a 'very big' problem, TM provided the greatest benefit at 3 months. For these latter patients, results were about the same between groups at 6 months, and improvement for TRT was much greater at 12 months, with further gains at 18 months.

Chronic tinnitus as phantom auditory pain.

OBJECTIVES: To investigate similarities between patients who experience chronic tinnitus or pain and to formulate treatment strategies that are likely to be effective for patients who experience phantom auditory pain. STUDY DESIGN: A total of 160 patients rated the severity and loudness of their tinnitus and completed the State-Trait Anxiety Inventory (STAI) and an abbreviated version of the Beck Depression Inventory (aBDI). Patients received counseling, audiometric testing, and matched the loudness of their tinnitus to sounds played through headphones. SETTING: A specialized tinnitus clinic within an urban medical center. RESULTS: Tinnitus severity was highly correlated with patients' degree of sleep disturbance, STAI, and aBDI scores. The self-rated (on a 1-to-10 scale)--but not the matched--loudness of tinnitus was correlated with tinnitus severity, sleep disturbance, STAI, and aBDI scores. CONCLUSIONS: The severity of chronic tinnitus is correlated with the severity of insomnia, anxiety, and depression. These relationships are the same for many patients with chronic pain. Treatment recommendations are discussed in reference to these results.

Tinnitus and insomnia.

PURPOSE: To investigate the effects of insomnia on tinnitus severity and to determine how this relationship may evolve with the passage of time. MATERIALS AND METHODS: Questionnaires were mailed to patients before their initial appointment at the Oregon Health Sciences University Tinnitus Clinic between 1994 and 1997. These questionnaires requested information pertaining to insomnia, tinnitus severity, and loudness. During their initial appointment, patients received counseling, education, and reassurance about tinnitus; audiometric and tinnitus evaluations; and treatment recommendations. Follow-up questionnaires were mailed to 350 patients 1 to 4 years (mean = 2.3 yr) after their initial appointment at the clinic. RESULTS: One hundred seventy-four patients (130 men, 44 women; mean age 55.9 yr) returned follow-up questionnaires. Although many of these patients improved in both sleep interference and tinnitus severity, a significant number (43) reported on the follow-up questionnaire that they continued to have difficulty sleeping. Reported loudness and severity of tinnitus were significantly greater for this group than for groups of patients who reported that they never or only sometimes have difficulty sleeping. The relationship between sleep disturbance and tinnitus severity became more pronounced with the passage of time. CONCLUSIONS: Insomnia is associated with greater perceived loudness and severity of tinnitus. These findings underscore the importance of identification and successful treatment of insomnia for patients with tinnitus.

Tinnitus severity, loudness, and depression.

Answers to questionnaires filled out by 436 patients who visited our tinnitus clinic were analyzed. Patients were asked to report the presence or absence of depression and to rate the loudness and severity of their tinnitus. Responses to questions about tinnitus loudness and severity from 121 patients who reported current depression were compared with responses from 285 patients who reported no history of depression. There was no significant difference in reported loudness of tinnitus between patients with and without depression. However, patients with current depression scored significantly higher than patients without depression on all 12 questions relating to tinnitus severity. We conclude that depression and tinnitus severity are linked in some patients. Treatment of depression with medications and psychotherapy is likely to reduce tinnitus severity for many of these patients.

Tinnitus as an early indicator of permanent hearing loss. A 15 year longitudinal study of noise exposed workers.

A retrospective study was designed to evaluate tinnitus (ringing or other sounds in the ears or head) as a potential early indicator of permanent hearing loss in a population of noise exposed workers. Data were examined from 91 male employees working in environments with noise levels ranging from 8 hour time weighted averages of 85 to 101 dBA over a period of 15 years. Results of annual audiometric testing were obtained as part of an ongoing hearing conservation program conducted since 1971 by ESCO Corporation, a steel foundry located in the Portland, Oregon metropolitan area. Results indicate the prevalence of tinnitus increases more than two and one half times for workers experiencing maximum threshold shifts > or = 15 decibels in hearing level (dBHL). Results also provide evidence that reports of tinnitus at the time of annual audiometric testing may be useful in identifying workers at greater risk for developing significant shifts in hearing thresholds.

Attributes of tinnitus that may predict temporomandibular joint dysfunction.

A collection of 1002 patients with severe tinnitus, drawn from the Tinnitus Data Registry, were retrospectively surveyed to determine which traits or attributes of tinnitus could indicate the possibility of temporomandibular joint dysfunction (TMD) as the cause of tinnitus. The patients were divided into two groups: (1) a TMD group, consisting of 69 patients for whom there was no known cause of tinnitus except for one or more temporomandibular joint (TMJ) indicators, and (2) a comparison group with mixed etiologies (n = 860). Seventy-three patients were eliminated due to excessive complications relating to cause. The two groups were compared seeking those attributes of tinnitus that significantly separated them. No single benchmark standard was discovered that exclusively indicated tinnitus from TMJ origins. However, a total of 10 "TMJ Indicators" were discovered. The data for each of these indicators is presented and discussed. In addition, the attributes that did not significantly separate the two groups are listed. The study concludes with a recommendation for TMJ referral for those tinnitus patients with unknown etiology who demonstrate any three or more of the TMJ indicators.

Attributes of tinnitus and the acceptance of masking.

Various characteristics of tinnitus were surveyed to determine whether they were associated with the acceptance of masking, which is used as a relief procedure for tinnitus. The characteristics considered were duration, loudness match, minimum masking level, and residual inhibition. Data for the characteristics of tinnitus were obtained from the Tinnitus Data Registry at the Oregon Hearing Research Center, which contains information on 784 tinnitus patients. The acceptance of masking was determined by each individual patient based on actual tests with wearable masking units. Variations in the individual characteristics listed above were not found to be significantly associated with the acceptance of masking and thus should not be used a priori to deny patients the opportunity for possible relief of their tinnitus. A masking indicator was found to be significantly (P = .03) associated with the acceptance of masking. This masking indicator is obtained by subtracting the loudness match of the tinnitus from the minimum masking level. When the masking indicator was 10 dB or less, the acceptance of masking was in excess of 50%. The data presented may help to dispel some current misconceptions about the masking of tinnitus.