Thesis (M. Aud.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 57-63).

Hearing loss is a disability that affects thousands of people in the world. It is estimated that there is 400,000 people with hearing difficulties in New Zealand (New Zealand Audiological Society, 2007). People with hearing loss have the right to access to information and communication (United Nations Enable, 2003). Without access to information and communication, the hearing impaired may encounter problems with emotional and social functioning, and consequently suffer with decreased quality of life. Clinical experience and investigations have revealed success with assistive listening devices (ALDs) where use of hearing aids has been unsuccessful. ALDs are devices that improve the communication function for the hearing impaired. ALDs can be used with or without hearing aids to overcome the negative effects of poor room acoustics. Currently, in the literature, little is known about the use and maintenance of ALDs in community organizations. This study investigates the use and maintenance of ALDs in the Christchurch community of New Zealand. A list of community organizations that provide ALDs to the public of Christchurch was also made available to individuals who have hearing impairment. The study found there is a lack of ALDs within the Christchurch community. Also that current ALD technology within the Christchurch community is not necessarily compatible with current hearing aid technology and that most organizations rely too heavily on PA systems. PA systems do not necessarily meet the needs of the hearing impaired and an ALD specifically targeting their hearing loss would improve their speech perception. Community organizations are not advertising enough that they offer ALDs which adds to the lack of awareness in Christchurch. Results found that most ALDs in the Christchurch community are in working order, however, there is a need for organizations to be educated about their use and maintenance. Audiologists and other health professionals have a key role in providing appropriate recommendations in the use and benefits that ALDs have on speech perception. These will directly improve the listening situations that the hearing impaired have throughout their communities, thus improving their quality of life.

Hearing loss is a disability that affects thousands of people in the world. It is estimated that there is 400,000 people with hearing difficulties in New Zealand (New Zealand Audiological Society, 2007). People with hearing loss have the right to access to information and communication (United Nations Enable, 2003). Without access to information and communication, the hearing impaired may encounter problems with emotional and social functioning, and consequently suffer with decreased quality of life. Clinical experience and investigations have revealed success with assistive listening devices (ALDs) where use of hearing aids has been unsuccessful. ALDs are devices that improve the communication function for the hearing impaired. ALDs can be used with or without hearing aids to overcome the negative effects of poor room acoustics. Currently, in the literature, little is known about the use and maintenance of ALDs in community organizations. This study investigates the use and maintenance of ALDs in the Christchurch community of New Zealand. A list of community organizations that provide ALDs to the public of Christchurch was also made available to individuals who have hearing impairment. The study found there is a lack of ALDs within the Christchurch community. Also that current ALD technology within the Christchurch community is not necessarily compatible with current hearing aid technology and that most organizations rely too heavily on PA systems. PA systems do not necessarily meet the needs of the hearing impaired and an ALD specifically targeting their hearing loss would improve their speech perception. Community organizations are not advertising enough that they offer ALDs which adds to the lack of awareness in Christchurch. Results found that most ALDs in the Christchurch community are in working order, however, there is a need for organizations to be educated about their use and maintenance. Audiologists and other health professionals have a key role in providing appropriate recommendations in the use and benefits that ALDs have on speech perception. These will directly improve the listening situations that the hearing impaired have throughout their communities, thus improving their quality of life.

To facilitate participation in hearing situations at work sites persons with hearing loss may use assistive listening devices (ALDs). Compared to personal hearing aids ALDs have received little research attention. The aim of this study was dual; firstly to describe ALD-users in Sweden and the usefulness of various equipment in relation to specified hearing situations at work. Secondly, to describe favorable and non favorable conditions for using ADL at everyday situations at work. Seventy ADL-users answered a questionnaire and eleven of these persons were subsequently interviewed. The concept of stigma has been identified in research on hearing loss as a strong factor of denial and resistance for the use of both hearing aids and ALDs, depending on the negative connotations related to visible means for hearing. In this study overcoming stigmatization was further analyzed using social recognition as a theoretical approach. In a concluding discussion, where both categorizations and themes from the interviews were used, it issuggested that the use of visible ALDs is a way of overcoming stigmatization and that their visibility function as a mechanism in developing mutual social recognition in the work group.Though the results show a fairly high degree of usefulness from ALDs, work place adaptations should to a greater extent pay attention to environmental factors (e.g. noise and bad acoustics) influencing the use of this technology. More information on such factors is needed from studies of realistic situations at concrete work sites. Conclusions from this study are mainly valid for this sample; knowledge of the population is small due to lack of registers kept by the providers of this technology. To facilitate further studies on employed persons with hearing loss available statistics could be significantly improved by keeping records on both medical data and all kinds of rehabilitative adaptations measures.

Background: Hearing aid prescriptive recommendations for hearing losses having a conductive component have received less clinical and research interest than for losses of a sensorineural nature; as a result, much variation remains among current prescriptive methods in their recommendations for conductive and mixed hearing losses (Johnson and Dillon, 2011). Purpose: The primary intent of this brief clinical note is to demonstrate differences between two algebraically equivalent expressions of hearing loss, which have been approaches used historically to generate a prescription for hearing losses with a conductive component. When air and bone conduction thresholds are entered into hearing aid prescriptions designed for nonlinear hearing aids, it was hypothesized that that two expressions would not yield equivalent amounts of prescribed insertion gain and output. These differences are examined for their impact on the maximum power output (MPO) requirements of the hearing aid. Subsequently, the MPO capabilities of two common behind-the-ear (BTE) receiver placement alternatives, receiver-in-aid (RIA) and receiver-in-canal (RIC), are examined. Study Samples: The two expressions of hearing losses examined were the 25% ABG + AC approach and the 75% ABG + BC approach, where ABG refers to air-bone gap, AC refers to air-conduction threshold, and BC refers to bone-conduction threshold. Example hearing loss cases with a conductive component are sampled for calculations. The MPO capabilities of the BTE receiver placements in commercially-available products were obtained from hearing aids on the U.S. federal purchasing contract. Results: Prescribed gain and the required MPO differs markedly between the two approaches. The 75% ABG + BC approach prescribes a compression ratio that is reflective of the amount of sensorineural hearing loss. Not all hearing aids will have the MPO capabilities to support the output requirements for fitting hearing losses with a large conductive component particularly when combined with significant sensorineural hearing loss. Generally, current RIA BTE products have greater output capabilities than RIC BTE products. Conclusions: The 75% ABG + BC approach is more appropriate than the 25% ABG + AC approach because the latter approach inappropriately uses AC thresholds as the basis for determining the compression ratio. That is, for hearing losses with a conductive component, the AC thresholds are not a measure of sensorineural hearing loss and cannot serve as the basis for determining the amount of desired compression. The Australian National Acoustic Laboratories has been using the 75% ABG + BC approach in lieu of the 25% ABG + AC approach since its release of the National Acoustic Laboratories—Non-linear 1 (NAL-NL1) prescriptive method in 1999. Future research may examine whether individuals with conductive hearing loss benefit or prefer more than 75% restoration of the conductive component provided adequate MPO capabilities to support such restoration.