Evaluating psychoacoustic measures for establishing presence of tinnitus

INTRODUCTION Chronic tinnitus is the persistent perception of sound that has no external source. Numerous studies indicate that tinnitus is experienced by 10-15 percent of adults [1]. An estimated 3-4 million U.S. military Veterans have tinnitus, of whom up to 1 million require clinical intervention [2]. It was recently reported that Veterans have twice the prevalence of tinnitus as non-Veterans [3]. The greater prevalence of tinnitus for Veterans compared with non-Veterans has also been reported by Adams et al. [4]. It would seem likely that noise exposure in the military (weapons fire, aircraft, explosions, etc.) increases the prevalence of tinnitus in Veterans [5]. Veterans can claim tinnitus as a service-connected disability. When approved, tinnitus claims nearly always result in a 10 percent disability rating, which qualifies the claimant for monthly compensation. The numbers of tinnitus disability claims have increased dramatically in the last 10 yr, and according to the Veterans Benefits Administration, tinnitus has been the most prevalent service-connected disability since 2008 (www.vba.va.gov/reports/abr/index.asp). During fiscal year 2011, 87,621 Veterans were awarded a new tinnitus service connection. By the end of fiscal year 2011, a total of 840,865 Veterans were service connected for tinnitus. Tinnitus is clearly a significant and escalating problem for Veterans and for the Department of Veterans Affairs (VA) healthcare system. Numerous factors have increased the problem of tinnitus for the Veterans Health Administration (VHA): 1. A series of changes in Federal regulations, beginning with Public Law 104-262, the Veterans Health Care Eligibility Reform Act of 1996, and concluding with VHA Directive 2008-070 resulted in many more Veterans being eligible for VA audiology services, including the provision of hearing aids. 2. In 1999, the definition of tinnitus was changed from "persistent" tinnitus due to hearing loss, head injury, or concussion to "recurrent" (occurring repeatedly) tinnitus due to any medical condition. 3. The proliferation of books, Web sites, and organizations focusing on tinnitus has increased its visibility as a legitimate medical condition. Veterans are more aware of tinnitus and are increasingly submitting disability claims and requesting services at VA medical centers. Patients reporting tinnitus are generally taken at their word because there would normally be no reason to dispute their complaint. Some patients, however, seek documentation to support a claim for financial compensation or to become eligible for medical services. The examiner must possess the skills to conduct such an assessment and to make qualified judgments as to the legitimacy of such claims [6]. The examiner's task is to verify whether the patient's claim is accurate and honest [7]. Performing a tinnitus assessment for litigation purposes can be a complex matter. The assessment involves several components, with each component requiring the examiner to make a decision based entirely on the claimant's subjective report. These components generally include assessing the presence, impact, etiology, and permanency of tinnitus [8]. No objective measure currently exists to prove the presence of chronic tinnitus or to verify its reported severity [5, 9-10]. Assessing tinnitus is similar to assessing pain, which depends on self-report, scaling of the subjective symptom, and medical history [11]. Assessing tinnitus for litigation purposes typically involves establishing consistency between verbal responses and medical records, reliability of tinnitus psychoacoustic measures, and sufficient duration of the tinnitus to assume permanency [8]. There is further the question of functional effects (impact, distress, reactions, etc.) of the tinnitus [12]. With the VA, however, functional effects are not considered when assessing a tinnitus claim. Only two nonfunctional factors are considered when assessing a Veteran's claim of tinnitus as a service-connected disability: (1) the tinnitus must be at least recurrent (intermittent) and (2) the tinnitus must be caused by some experience while in the military (e. …