Publications by Year: 2005

Both clinical and research findings support the effectiveness of frequency-modulated (FM) technology among individuals who continue to encounter significant communication problems despite the use of conventional hearing instruments. The use rate of FM devices throughout the nation, however, remains disappointingly low. The authors present a case of a longtime hearing aid user whose hearing aids provided decreasing benefit as his hearing impairment increased to the extent that cochlear implantation was considered. Through the establishment of patient-specific treatment goals, the provision of appropriate FM technology as verified through real-ear measurements, and careful and deliberate counseling and follow-up, this patient was able to realize significant communication benefits as reported through several self-assessment measures. The cost-benefit implications of FM technology versus cochlear implantation are discussed.

The World Health Organization's (WHO) Disability Assessment Scale II (WHO-DAS II) is a generic health-status instrument firmly grounded in the WHO's International Classification of Functioning, Disability and Health (WHO-ICF). As such, it assesses functioning for six domains: communication, mobility, self-care, interpersonal, life activities, and participation. Domain scores aggregate to a total score. Because the WHO-DAS II contains questions relevant to hearing and communication, it has good face validity for use as an outcome measure for audiologic intervention. The purpose of the present study was to determine the psychometric properties of the WHO-DAS II on a sample of individuals with adult-onset hearing loss, including convergent validity, internal consistency, and test-retest stability. Convergent validity was established by examining correlations between the WHO-DAS II (domain and total scores) and the Abbreviated Profile of Hearing Aid Benefit (APHAB) and the Hearing Aid Handicap for the Elderly (HHIE), two disease-specific measures, as well as with the Short Form-36 for veterans (SF-36V), a second generic measure. Data on all four measures were collected from 380 older individuals with adult-onset hearing loss who were not hearing aid users. The results of the convergent validity analysis revealed that the WHODAS II communication domain score was moderately and significantly correlated with scores on the APHAB and the HHIE. WHO-DAS II interpersonal and participation domain scores and the total scores were also moderately and significantly correlated with HHIE scores. These findings support the validity of using the WHO-DAS II for assessing activity limitations and participation restrictions of adult-onset hearing loss. Several WHO-DAS II domain scores and the total score were also significantly and moderately-markedly correlated with scores from the SF-36V. These findings support the validity of the WHO-DAS II as a generic health-status instrument. Internal consistency reliability for all the domain scores was adequate for all but the interpersonal domain. Test-retest stability for all the domain scores was adequate. Critical difference values were calculated for use in clinical application of the WHO-DAS II. From these findings, we concluded that the WHO-DAS II communication, participation, and total scores can be used to examine the effects of adult-onset hearing loss on functional health status. Further work examining the utility of the WHO-DAS II as an outcome measure for hearing aid intervention is warranted.

The World Health Organization's Disability Assessment Scale II (WHO-DAS II) is a generic health-status instrument that provides six domain scores and a total, aggregate score. Two of the domain scores, communication and participation, and the total score, have good validity, internal-consistency reliability, and test-retest stability in individuals with adult-onset hearing loss. As such, these two domain scores and the total WHO-DAS II score may be useful as generic outcome measures to assess the effectiveness of hearing aid intervention for this population. Before the use of the WHO-DAS II in hearing aid clinical trials, however, the responsiveness of the instrument and the short- and long-term outcomes to hearing aid intervention had to be determined. Responsiveness and outcomes were assessed in 380 veterans (approximately half received hearing aids and half served as controls) by examining group differences, effect-size estimates, and individual differences as a function of hearing aid intervention. For comparison, data also were obtained on two disease-specific measures, the APHAB and the HHIE. The WHO-DAS II communication domain and total scores were sufficiently responsive to hearing aid intervention for use in future studies in which group differences are to be detected. The WHO-DAS II participation domain was not sufficiently responsive to hearing aid intervention. The APHAB and HHIE, both disease-specific measures, were more sensitive to hearing aid intervention than the generic measure. The short- and long-term outcomes of hearing aid intervention were also examined in the present study. Group outcomes for hearing aid intervention can be expected to be stable for at least 6 months when measured by WHO-DAS II total score and for at least 12 months when measured by the WHO-DAS II communication domain scores. Effect-size estimates and examination of the number of individuals exhibiting change scores exceeding 90% critical differences for true changes in scores indicate that for clinical applications, disease-specific instruments are more useful than the WHO-DAS II. The findings of this study support the use of the WHO-DAS II as a generic measure in hearing aid trials research so as to allow for comparisons of health-status outcomes across different diseases or disorders.

Health-related quality-of-life (HRQoL) instruments measure the impact of a disorder and treatment on several attributes that are thought to constitute the self-perceived health status of an individual. This tutorial reviews the conceptual framework of HRQoL, including the challenges associated with defining and measuring HRQoL, specifically as it applies to audiologic care. A relatively new instrument, the World Health Organization-Disability Assessment Schedule II, will be discussed as a potentially valuable instrument to measure the impact of hearing loss and hearing aid intervention on self-perceived HRQoL.