Development of Telscreen: a telephone-based speech-in-noise hearing screening test with a novel masking noise and scoring procedure.

OBJECTIVE: In 2006 the National Acoustic Laboratories was commissioned to create a telephone-based hearing screening test. DESIGN: NAL developed 'Telscreen', a speech-in-noise test modelled on the Dutch and UK telephone tests. The first version, Telscreen I, had several novel features: individual scoring of digits; individual equalization of digit intelligibility; and accuracy-determined test termination. Evaluation of Telscreen I revealed that it did not discriminate satisfactorily between those with and without hearing impairment. Subsequently Telscreen II, which included a novel sensitized masking noise, was developed. STUDY SAMPLE: Telscreen I was evaluated by 105 participants (22-86 years), 37% with normal hearing (all thresholds <20 dB HL in the test ear), 63% with hearing impairment (all thresholds >20 dB HL in the test ear). Telscreen II was evaluated by 75 participants (25-86 years), 33% with normal hearing, 67% with hearing impairment. RESULTS: Correlations between Telscreen I results and hearing thresholds, r = 0.57, and hearing disability scores, r = 0.51 were highly significant, but lower than expected. Correlations for Telscreen II were higher: r = 0.77 and 0.65, respectively. Telscreen II was found to have high sensitivity: 90%; and specificity: 90.2%. CONCLUSIONS: Telscreen II is an efficient, reliable, and innovative hearing screening test that provides a solid foundation for future tests delivered via mobile and internet technologies.

The detection of infant cortical auditory evoked potentials (CAEPs) using statistical and visual detection techniques.

BACKGROUND: With the advent of newborn hearing screening programs, the need to verify the fit of hearing aids in young infants has increased. The recording of cortical auditory evoked potentials (CAEPs) for this purpose is quite feasible, but rapid developmental changes that affect response morphology and the presence of electrophysiological noise can make subjective response detection challenging. PURPOSE: The purpose of this study was to investigate the effectiveness of an automated statistic versus experienced examiners in detecting the presence of infant CAEPs when stimuli were present and reporting the absence of CAEPs when no stimuli were present. RESEARCH DESIGN: A repeated-measures design was used where infant-generated CAEPs were interpreted by examiners and an automated statistic. STUDY SAMPLE: There were nine male and five female infants (mean age, 12 mo; SD, 3.4) who completed behavioral and electrophysiological testing using speech-based stimuli. DATA COLLECTION AND ANALYSIS: In total, 87 infant CAEPs were recorded to three sensation levels, 10, 20 and 30 dB relative to the behavioral thresholds and to nonstimulus trials. Three examiners were presented with these responses: (1) "in series," where waveforms were presented in order of decreasing stimulus presentation levels, and (2) "nonseries," where waveforms were randomized completely and presented as independent waveforms. The examiners were given no information about the stimulus levels and were asked to determine whether responses to auditory stimulation could be observed and their degree of certainty in making their decision. Data from the CAEP responses were also converted to multiple dependent variables and analyzed using Hotelling's T(2). Results from both methods of response detection were analyzed using a repeated measures ANOVA (analysis of variance) and parameters of signal detection theory known as d-prime (d') and the area under the receiver operating characteristic (ROC) curve. RESULTS: Results showed that as the stimulus level increased, the sensitivity index, d', increased for both methods of response detection, but neither reached the maximum possible d' value with a sensation level of 30 dB. The examiners with the greatest experience and Hotelling's T(2) were equally sensitive in differentiating the CAEP from noise. CONCLUSIONS: Hotelling's T(2) appears to detect CAEPs from normal hearing infants at a rate equal to that of an experienced examiner. A clinical instrument that applies Hotelling's T(2) on-line, so that the likelihood of response detection can be assessed objectively, should be of particular benefit to the novice or less experienced examiner.

Use of hearing AIDS and assistive listening devices in an older Australian population.

BACKGROUND: Hearing loss is a common sensory impairment experienced by older persons. Evidence shows that the use of hearing aids and/or assistive listening devices (ALDs) can benefit those with a hearing loss but that historically the uptake and use of these technologies has remained relatively low compared with the number of people who report a hearing loss. PURPOSE: The aim of this study was to determine the prevalence, usage, and factors associated with the use of hearing aids and ALDs in an older representative Australian population. RESEARCH DESIGN: A population-based survey. STUDY SAMPLE: A total of 2956 persons out of 3914 eligible people between the ages of 49 and 99 yr (mean age 67.4 yr), living in the Blue Mountains, west of Sydney, completed a hearing study conducted from 1997 to 2003. DATA COLLECTION AND ANALYSIS: Hearing levels were assessed using pure tone audiometry, and subjects were administered a comprehensive hearing survey by audiologists, which included questions about hearing aid and ALD usage. Logistic regression analysis was used to identify factors associated with hearing aid and ALD usage. RESULTS: Of the surveyed population, 33% had a hearing loss as measured in the better ear. 4.4% had used an ALD in the past 12 mo, and 11% owned a hearing aid. Of current hearing aid owners, 24% never used their aids. ALD and hearing aid usage were found to be associated with increasing age, hearing loss, and self-perceived hearing disability. CONCLUSIONS: These results indicate that hearing aid ownership and ALD usage remains low in the older population. Given the significant proportion of older people who self-report and have a measured hearing loss, it is possible that more could be helped through the increased use of hearing aid and/or ALD technology. Greater efforts are needed to promote the benefits of these technologies and to support their use among older people with hearing loss.

The detection of adult cortical auditory evoked potentials (CAEPs) using an automated statistic and visual detection.

The detection of adult cortical auditory evoked potentials (CAEPs) can be challenging when the stimulus is just audible. The effectiveness of a statistic compared with expert examiners in (1) detecting the presence of CAEPs when stimuli were present, and (2) reporting the absence of CAEPs when no stimuli were present, was investigated. CAEPs recorded from ten adults, using two speech-based stimuli, five stimulus presentation levels, and non-stimulus conditions, were given to four experienced examiners who were asked to determine if responses to auditory stimulation could be observed, and their degree of certainty in making their decision. These recordings were also converted to multiple dependent variables and Hotelling's T2 was applied to calculate the probability that the mean value of any linear combination of these variables was significantly different from zero. Results showed that Hotelling's T2 was equally sensitive to the best of individual experienced examiners in differentiating a CAEP from random noise. It is reasonable to assume that the difference in response detection for a novice examiner and Hotelling's T2 would be even greater.

Cortical auditory evoked potentials in the assessment of auditory neuropathy: two case studies.

Infants with auditory neuropathy and possible hearing impairment are being identified at very young ages through the implementation of hearing screening programs. The diagnosis is commonly based on evidence of normal cochlear function but abnormal brainstem function. This lack of normal brainstem function is highly problematic when prescribing amplification in young infants because prescriptive formulae require the input of hearing thresholds that are normally estimated from auditory brainstem responses to tonal stimuli. Without this information, there is great uncertainty surrounding the final fitting. Cortical auditory evoked potentials may, however, still be evident and reliably recorded to speech stimuli presented at conversational levels. The case studies of two infants are presented that demonstrate how these higher order electrophysiological responses may be utilized in the audiological management of some infants with auditory neuropathy.

Tympanometric and acoustic stapedius reflex measures in older adults: the Blue Mountains Hearing Study.

Tympanometric peak pressure, peak compensated static acoustic admittance (peak Ytm) and acoustic stapedius reflex (ASR) thresholds were obtained for a representative sample of 1565 older Australians who were participants in the Blue Mountains Hearing Study (BMHS). No significant age or gender effects were found for tympanometric peak pressure. Peak Ytm measures, however, decreased with age in the left ear only across all age groups and were consistently higher for men than for women. After allowing for hearing loss, the effect of age on ASR thresholds was inconsistent. An increase in ASR thresholds with age was observed at selected frequencies but only when measured contralaterally, and these changes were not clinically significant. Overall, our findings suggest that current normative data for peak Ytm is too restricted for application in the older population, but there is insufficient evidence to warrant alternative normative data for the ASR threshold range in this same population.

The relationship between obligatory cortical auditory evoked potentials (CAEPs) and functional measures in young infants.

Finding ways to evaluate the success of hearing aid fittings in young infants has increased in importance with the implementation of hearing screening programs. Cortical auditory evoked potentials (CAEP) can be recorded in infants and provides evidence for speech detection at the cortical level. The validity of this technique as a tool of hearing aid evaluation needs, however, to be demonstrated. The present study examined the relationship between the presence/absence of CAEPs to speech stimuli and the outcomes of a parental questionnaire in young infants who were fitted with hearing aids. The presence/absence of responses was determined by an experienced examiner as well as by a statistical measure, Hotelling's T(2). A statistically significant correlation between CAEPs and questionnaire scores was found using the examiner's grading (rs = 0.45) and using the statistical grading (rs = 0.41), and there was reasonably good agreement between traditional response detection methods and the statistical analysis.

Association between vision and hearing impairments and their combined effects on quality of life.

OBJECTIVES: To assess associations between age-related vision and hearing impairments and whether combined sensory losses magnify effects on health-related quality of life. METHODS: Seventy-five percent of survivors (n = 2334) were reexamined at Blue Mountains Eye Study 5-year examinations and 86.3% (2015) attended hearing assessments. Visual impairment was defined as visual acuity less than 20/40 (better eye), and hearing impairment as average pure-tone air conduction threshold greater than 25 dB (500-4000 Hz, better ear). RESULTS: Persons with visual impairment, compared with those without visual impairment, had lower mean audiometric thresholds across all frequencies (P< or =.05). For each 1-line (5-letter) reduction in best-corrected visual acuity and presenting visual acuity, hearing loss prevalence increased by 18% and 13%, respectively. Cataract and age-related maculopathy were also associated with hearing loss (respectively, multivariate-adjusted odds ratio, 1.3 and 1.6; 95% confidence interval, 1.0-1.7 and 1.1-3.1). The association between age-related maculopathy and hearing loss was stronger at younger ages (<70 years). Combined impairments were associated with poorer health-related quality of life than were single impairments (multivariate-adjusted 36-Item Short-Form Health Survey mean physical and mental component scores; Ptrend = .001 and <.001, respectively). CONCLUSIONS: Older persons with visual impairment were also more likely to have hearing loss in this study, which suggests that these sensory impairments could share common risk factors or biologic aging markers. Combined sensory impairments also cumulatively affect health-related quality of life.

Odds of demonstrating auditory processing abnormality in the average older adult: the Blue Mountains Hearing Study.

OBJECTIVE: To determine, for the average older adult, the odds of demonstrating an auditory processing abnormality for each of seven speech-based measures of auditory processing and how these odds vary based on a number of independent subject variables. DESIGN: Using a cross-sectional design, 1576 adults aged 55 years and older were assessed with speech measures of central auditory processing and questionnaires pertaining to health status, cognitive and perceived auditory function. The speech-based measures from which abnormal/normal outcomes were derived were (a) right ear Macquarie Synthetic Sentence Identification (MSSI) test maximum performance score (Rt MSSImax), (b) left ear MSSI test maximum performance score (Lt MSSImax), (c) right ear Macquarie Dichotic Sentence Identification (MDSI) test score (Rt MDSI), (d) left ear MDSI test score (Lt MDSI), (e) difference score for the right and left ear MDSI test (MDSI Diff score), (f) right ear MSSI test maximum performance score subtracted from the maximum performance score for monosyllabic word list materials in the same ear (Rt PB-MSSImax), and (g) left ear MSSI test maximum performance score subtracted from the maximum performance score for monosyllabic word list materials in the same ear (Lt PB-MSSImax). RESULTS: The odds of demonstrating auditory processing abnormality for average older participants, increased by 4 to 9% per year of age. Men were approximately twice as likely as women to demonstrate this abnormality, but the gender difference was only evident with dichotic measures. With increasing hearing handicap, the odds of demonstrating auditory processing abnormality increased, but this was only evident for speech-in-noise measures. With subtle cognitive decline, the odds of demonstrating auditory processing abnormality also increased. CONCLUSIONS: This population-based study provides evidence of a link between perceived hearing handicap and outcomes on speech-in-noise measures as well as evidence of a gender difference that became apparent using dichotic tests. The contribution of central auditory processing abnormality to hearing health should therefore not be overlooked in the provision of auditory rehabilitation programs to older adults.

Risk markers for the graded severity of auditory processing abnormality in an older Australian population: the Blue Mountains Hearing Study.

A recent report from a population-based survey of hearing loss in 2015 older adults showed that the overall prevalence of central auditory processing (CAP) abnormality was high at 76.4% using abnormality on one or more of seven speech-based test outcomes as the criteria. The present study grouped these test outcomes to reflect increasing severity of CAP abnormality and examined the relationship between this graded dependent variable and 16 independent variables. Logistic regression modeling suggested that moderate and severe CAP abnormality increased with age and was associated with increased hearing handicap, and men were more likely than women to show severe abnormality. While 98.5% of the population passed a cognitive screening assessment, declining cognitive function was still associated with the increased likelihood of CAP abnormality.

Prevalence of central auditory processing (CAP) abnormality in an older Australian population: the Blue Mountains Hearing Study.

Age-related central auditory processing (CAP) abnormality has been described in many studies with widely varying prevalence reported. To date, there has been only one population study to report prevalence for this age-related condition, and these rates were significantly lower than in reports from clinical studies. The present study reports findings from a recent population study in which 2015 Australians aged 55 years and older living in a defined area west of Sydney were assessed with a battery of behavioral and electrophysiological auditory tests. This battery included speech measures from which a high overall prevalence rate (76.4%) of CAP abnormalities was found, in keeping with previous clinical studies. While gender differences were dependent on the test measure, the number of abnormal test outcomes increased systematically with age. Hearing loss and abnormal cognitive function, however, did not systematically increase with number of abnormal test outcomes.

Factors predicting severity of tinnitus: a population-based assessment.

The Blue Mountains Hearing Study (BMHS) has shown that tinnitus affects one in three older Australians with 16% of cases describing severe annoyance. Among persons describing severe symptoms, 52% have sought professional help. We aim to identify factors associated with the severity of tinnitus in 2,015 persons aged over 54 years. Comprehensive questionnaires about hearing were administered. Air- (250-8000 Hz) and bone-conduction (500-4000 Hz) audiometric thresholds of both ears, together with transient evoked and spontaneous otoacoustic emissions, were measured. Factors predicting severity of tinnitus were assessed in Cox proportional hazard models. After multivariate adjustment, factors significantly associated with severe tinnitus were hearing loss (relative risk [RR] 2.9), dizziness (RR 2.0), head injury (RR 2.0), sinus and middle ear infections (RR 1.9), and mastoiditis (RR 3.9). Associations with mild tinnitus included age (RR 0.8), hearing loss (RR 1.4) and history of dizziness (RR 1.5), meningitis (RR 2.2), and migraine (RR 1.5). Knowledge of these factors could contribute to improved tinnitus management.

Risk factors for tinnitus in a population of older adults: the blue mountains hearing study.

OBJECTIVE: To identify potential and modifiable risk factors for tinnitus in a population of older adults. STUDY DESIGN: Cross-sectional study. Detailed questionnaires were interviewer-administered in a representative sample of 2015 persons aged 55+ yr, living in an area west of Sydney, Australia. Air- and bone-conduction audiometric thresholds were measured from 250 to 8000 Hz and from 500 to 4000 Hz, respectively. TEOAE and SOAE were measured for both ears. RESULTS: After adjusting for multiple variables in a Cox proportional hazards model, factors that significantly increased the risk of tinnitus were poorer hearing and cochlear function, self-reported work-related noise exposure, and history of middle ear or sinus infections, severe neck injury or migraine. CONCLUSION: Interventions aimed at reducing age-related hearing loss, particularly by reducing excessive work-related noise exposure, and the effective, timely treatment of ear-related infections, may all decrease the risk of tinnitus.

Prevalence and characteristics of tinnitus in older adults: the Blue Mountains Hearing Study.

There have been few recent estimates of the prevalence of tinnitus from large population-based samples of older persons. Our study aimed to assess the prevalence and characteristics of prolonged tinnitus in a representative sample of 2015 adults aged 55-99 years, residing in the Blue Mountains, west of Sydney, Australia, during 1997-99. All participants underwent a detailed hearing examination by an audiologist, including comprehensive questions about hearing. After age adjustment, subjects reporting tinnitus had significantly worse hearing at both lower and higher frequencies (p < 0.001). This difference was more marked in younger than in older subjects (p < 0.05). Overall, 602 subjects (30.3%) reported having experienced tinnitus, with 48% reporting symptoms in both ears. Tinnitus had been present for at least 6 years in 50% of cases, and most (55%) reported a gradual onset. Despite tinnitus being described as mildly to extremely annoying by 67%, only 37% had sought professional help, and only 6% had received any treatment.