Abstract
The presence of hearing loss has many consequences for the affected individual. The most obvious effect of hearing loss is on hearing acuity and on communication function. The need for a more global view of the effects of hearing loss has led to the supplementation of traditional measures of auditory sensitivity and speech recognition performance by measures of perceived disability or handicap.
Standardized questionnaires such as the Abbreviated Profile of Hearing Aid Benefit (APHAB) (Cox and Alexander, 1995) can provide information about the disability resulting from hearing loss and allows quantification of the change in disability through hearing aid use. Questionnaires such as the Hearing Handicap Inventory for the Elderly (Ventry and Weinstein, 1982) provide information about the emotional and social consequences of hearing loss. Readministration of the questionnaire after audiologic rehabilitation (i.e., hearing aids, cochlear implants, assistive listening devices, aural rehabilitation) can be used to document improvements in emotional and social function.
Questionnaires developed specifically to quantify the effects of hearing loss are very useful, but they do not fully assess the impact of hearing loss on quality of life because they focus almost exclusively on communication function. The relationship between hearing loss and quality of life has been documented by the use of more global or generic measures of functional health. Generic measures sensitive to the effects of hearing loss would allow a comparison of the consequences of hearing loss with other disorders or illnesses, would enable documentation of the benefit of intervention with the same instrument used for assessing treatment of other disorders, and might be used to determine relative costs associated with treatment.
At a recent workshop dealing with the use of self-report measures in audiologic rehabilitation, the need for a generic test instrument sensitive to the effects of hearing loss and to audiologic intervention was identified (Bess, 2000). This issue of Trends in Amplification is devoted to the topic of assessing the impact of hearing loss and audiologic intervention on quality of life. The first paper, a tutorial by Harvey Abrams, provides an overview of the techniques used to assess the impact of a disease or disorder, or its treatment, on quality of life, and introduces the World Health Organization (WHO) model for classifying impairments, activities and participation and the WHO's Disability Assessment Scale II (WHO-DAS II).
The second and third papers (coauthored by Chisolm, Harvey Abrams, Rachel McArdle, Richard H. Wilson, and Patrick J. Doyle) describe the results of a large-scale study that evaluated the utility of the WHO-DAS II in measuring the effects of hearing loss and hearing intervention. The second paper describes the psychometric properties of the WHO-DAS II and the sensitivity of the instrument to the effects of adult-onset hearing loss. The third paper describes the responsiveness of the WHO-DAS II to hearing aid intervention and the relationship between the WHO-DAS II and two disease-specific instruments, the Abbreviated Profile of Hearing Aid Benefit and the Hearing Handicap Inventory for the Elderly.
In these reports, the group establishes that the WHO-DAS II is a useful generic test for examining the effects of adult-onset hearing loss on functional health status and for inclusion as a generic measure in hearing aid trials research that will facilitate comparisons of health-status outcomes with different diseases or disorders.
About the Authors
Harvey Abrams is the Chief of the Audiology and Speech Pathology Service, Veterans Affairs Medical Center, Bay Pines, FL, and is on the faculty of the Department of Communication Sciences & Disorders at the University of South Florida. He received his masters and doctoral degrees from the University of Florida. Dr Abrams is funded by the Rehabilitation Research and Development Service of the Department of Veterans Affairs to conduct research concerning treatment efficacy and improved quality of life associated with audiologic intervention. He has authored and coauthored several recent papers and book chapters and is a frequent lecturer on the topic of outcome measures and evidence-based audiologic practice.
Theresa Hnath Chisolm is Professor and Chair of the Department of Communication Sciences & Disorders at the University of South Florida. She received her doctoral degree from the Graduate School of the City University of New York and her masters in Audiology from Montclair State College. Dr Chisolm's research has been funded through the National Institutes of Health-National Institute on Deafness and Other Communication Disorders (NIDCD) and through the Rehabilitation Research and Development Service of the Department of Veterans Affairs. She has published extensively in the field of hearing aids and aural rehabilitation.
Patrick J. Doyle, PhD, is the Associate Director for Research of the Geriatric Research, Education and Clinical Center (GRECC), Director of Audiology/Speech Pathology Service at the VA Pittsburgh Healthcare System, and Associate Professor of Communication Science & Disorders, at the University of Pittsburgh. He served as a Visiting Scientist in the Assessment, Classification and Epidemiology Program at the WHO headquarters in Geneva, Switzerland, where he collaborated on the WHO-DAS II multicountry field trial. It was during this time that he developed the conceptual framework for the burden of stroke scale (the BOSS) whose psychometric properties have been published in the Journal of Clinical Epidemiology. Dr Doyle's current research program is focused on the assessment, quantification, and determinants of patient-reported functioning and well-being in stroke survivors with and without communication disorders.
Dr Rachel McArdle is a research audiologist at the VA Medical Center at Bay Pines, Florida. She received her masters and doctoral degrees from the University of South Florida. She is currently funded by the VA Rehabilitation Research and Development through a Research Career Development Award. Dr McArdle's research interests include speech perception in the aging adult and speech recognition ability in noise.
Dr Richard Wilson is a Senior Research Career Scientist at the James H. Quillen VA Medical Center in Mountain Home, TN, and a professor in the Department of Surgery at the James H. Quillen College of Medicine and at East Tennessee State University. He received his doctoral degree from Northwestern University. Dr Wilson has had a long, distinguished career and has published extensively on many different topics related to diagnostics and aural rehabilitation. Recently he was one of the researchers involved in the cooperative NIDCD/VA hearing aid clinical trial. He is also involved in the study of efficacy of digital noise reduction strategies, and in the study of functioning, disability, and quality of life in adult hearing impaired.