Validating stimuli for Estonian Digit Triplet hearing test

Käesoleva töö eesmärk oli hinnata ja valideerida stiimuleid eestikeelse Digit Triplet testi (DTT) väljatöötamise jaoks. Esmased pilootkatsed viidi läbi 12 erineva stiimuli ehk numbrikolmikuga. Töö käigus arvutati praeguste katses kasutatud stiimulite põhjal võimalikult head stiimuli karakteristikud, milleks on kõnetaju lävi (KTL) -9,79 dB ning regressioonikõvera tõus kõnetaju läve punktis 19,49%/dB. Sellega loodi ka esmane suund, millele olemasolevate stiimulite arendamisel või uute väljatöötamisel ja järgmiste pilootkatsete käigus tugineda. Kindlasti ei saa väita, et töö käigus leiti ideaalse stiimuli karakteristikud. Selleks on vaja madala eristusvõimega stiimuleid täiustada, et stiimulitevahelist hajuvust vähendada, ning kvaliteetsemate stiimulitega uued pilootkatsed läbi viia

Development of a Māori Language Version of the New Zealand Hearing Screening Test

Hearing loss has a prevalence of 10.3% in New Zealand, with the Māori population being disproportionately affected compared to the non-Māori population. Hearing loss is an impairment that is under-recognised, under-reported and under-treated. This can be explained by the many existing barriers – the shortage of audiological services, financial cost to an individual seeking treatment, the stigma of both hearing loss and hearing aids, and healthcare seeking rates, particularly among the Māori population. This study aimed to develop a Māori language adaptive digit triplet test that could be offered remotely via the telephone and Internet as a hearing-screening test. Three sets of recordings were made of digit triplets spoken in te reo Māori by a female speaker. Two of these sets were selected for normalisation in speech noise. Normal-hearing participants (8 listeners) with hearing thresholds ≤20 dB HL were tested to establish the intelligibility of the individual recorded digits at various signal-to-noise ratios (-13, -10.5, -8 and -5.5 dB). Psychometric functions were fitted to the intelligibility data, and the digits in each position of the triplet that had the steepest slope were selected as the final test stimuli. The level of each selected digit was then adjusted to achieve equal intelligibility as measured at the midpoints of the psychometric functions. These digits were then assembled into eight equivalent lists of similar difficulty, ready for pilot testing. Due to low participant numbers, the pilot testing phase was not completed. Further development of this test continues as the focus of a follow-on study

Improving the New Zealand Digit Triplet Test Using antiphasic stimuli.

Hearing impairment is a condition which affects many New Zealanders. The World Health Organization estimates that by the year 2050, 1 in every 4 people worldwide will suffer from a hearing impairment of some form (World Health Organization, 2021). As hearing impairment has been found to have negative consequences for both individuals and society at large, having widely available hearing screening tools is of growing importance. While traditional audiological testing is the gold standard for detecting a hearing impairment, this is not always available – particularly in rural or third world countries. As well as this, the recent outbreak of COVID-19 has highlighted the need of alternative testing methods which can be done in a socially-distanced manner (De Sousa, Smits, et al., 2020). This thesis looks to improve one such method of contactless testing available in New Zealand known as the New Zealand Hearing Screening Test, which uses a New Zealand English digit triplet test. Traditionally this and other digits-in-noise tests have used diotic stimuli (where identical stimuli are presented to both ears) and have been scored by triplet (where all three numbers in the triplet must be correctly entered). The present study investigated the use of antiphasic stimuli (where the polarity of the speech is reversed in one ear) which was shown by De Sousa, Swanepoel, et al. (2020) to improve the sensitivity and specificity of digits-in-noise testing. This study also investigated whether scoring by individual digit rather than digit triplet could also improve the ability of the test to distinguish between people with normal hearing and those with hearing impairment. Our results found that similar to De Sousa, Swanepoel, et al. (2020), the use of antiphasic stimuli increased the sensitivity and specificity of the New Zealand English digit triplet test from 94% and 88% to 95% and 90% respectively. However, scoring by digit rather than triplet was not found to improve test performance

Audiology and community-based rehabilitation in the Democratic Republic of the Congo: development of the first hearing screening tools for infants and children

Abstract This study is aimed at developing the first hearing test tool, adapted to national languages, for the early detection of children at risk of hearing loss in the DRC. Specific objectives included adapting and evaluating the effectiveness of the LittlEARS Auditory Questionnaire (LEAQ) as a screening tool for hearing loss in children aged 0–24 months in the DRC; constructing and validating the Kiswahili versions of the Adaptive Auditory Speech Test (AAST) for children aged 3–4 years and older; and determining the role of the LEAQ and the AAST as hearing screening tools in the community-based rehabilitation (CBR) programme. v Methods A cross-sectional design was used to select a total of 1.501 participants for the study. The sample included children, adolescents and adults including parents. For validation of the LEAQ, norm data were collected from (N=723) babies for the Lingala version and (N=648) babies for the Kiswahili version for children (0–24 months). In order to investigate the effectiveness of the LEAQ as a screening tool for children aged between 25–36 months, norm data was collected from (N=114) babies for the Lingala version and (N=82) babies for the Kiswahili version. In order to determine the Kiswahili version, AAST norm data were collected from N=130 (male: n=62, female: n=68). Results The results for the regression curve generated with age as an independent variable and total scores as dependent variables for the LEAQ showed the Kiswahili version as being very similar, r=0.81 (p=< 0.001) to the original German version r =0.91, and the Lingala version as being a little different but also very similar to the German version, r= 0.77 (p=< 0.001), whereby a value of 0.7 or higher shows a high correlation .These results legitimize the use of the LEAQ to screen for hearing loss in the DRC in infants and children from 1-24 months and vi above. The constructed version of the version of the Kiswahili Adaptive Auditory Speech Test (AAST) was used to find out the Speech Reception Threshold (SRT) in quiet and in noise conditions with the aim to determine the norm values in children aged 3-4 years and older. Conclusion The adapted Lingala and Kiswahili version of the LEAQ can be used for the screening and diagnosis of hearing loss in children under and over 3 years in the DRC. The study confirms that, the Kiswahili version of the AAST has an approximate difference of 10.2 dB observed between the year 4 old and 10 years old children in quiet, with a significant improve as the age increase. In addition, the LEAQ and the AAST can be used as screening tools in infants, but it may also be important to point out that, despite the UNHS being the gold standard , the procedures for these other 2 tests will represent an approximation if the UNHS cannot yet be introduced in the DRC due to cost and organizational reasons. This can have a positive implication by generating concrete data that will have considerable impact in influencing the legislation and integration of the LEAQ as a screening tool in the primary health care packag

Development of central auditory processes in Polish children and adolescents at the age from 7 to 16 years

There are discrepancies in the literature regarding the course of central auditory processes (CAP) maturation in typically developing children and adolescents. The purpose of the study was to provide an overview of age - related improvement in CAP in Polish primary and secondary school students aged 7–16 years. 180 children/adolescents, subdivided into 9 age categories, and 20 adults (aged 18-24 years) performed the Dichotic Digit Test (DDT), Duration Pattern Test (DPT), Frequency Pattern Test (FPT), Gap Detection Test (GDT) and adaptive Speech-in-Noise (aSpN). The 12-year-olds was retested after w week. We found the age effects only for the DDT, DPT and FPT. In the right ear DDT the 7-year-olds performed more poorly than all groups ≥12. In the left ear DDT both 7- and 8-year-olds achieved less correct responses compared with the 13-, 14-, 15- year-olds and with the adults. The right ear advantage was greater in the 7-year-olds than in the 15-year-olds and adult group. At the age of 7 there was lower DPT and FPT scores than in all participants ≥13 whereas the 8-year-olds obtained less correct responses in the FPT than all age categories ≥12. Almost all groups (except for the 7-year-olds) performed better in the DPT than FPT. The test-retest reliability for all tests was satisfactory. The study demonstrated that different CAP have their own patterns of improvement with age and some of them are specific for the Polish population. The psychoacoustic battery may be useful in screening for CAP disorders in Poland

Advanced applications in digits-in-noise testing to detect and differentiate hearing loss

More than half a billion people have disabling degrees of hearing loss, which, left untreated, has debilitating consequences to the individual and society. Prevalence is expected to increase rapidly within the next thirty years, making hearing loss a significant public health matter. Thus, increasing efforts should be made towards detection and treatment. Many people with hearing loss reside in low- and middle-income countries, where the capacity to provide care, especially clinic-based models of care, is limited. Furthermore, the inaccessibility has been exacerbated by the COVID-19 pandemic. The digits-in-noise (DIN) test has been a more accessible screening tool over the past two decades, measuring a speech recognition threshold (SRT) that has a high association with standard pure tone audiometry. The test has the benefit of being provided directly to the public over digital modes like smartphones, using familiar stimuli and a simple procedure that does not require calibration. One example is the hearWHO DIN test that has been widely used and promoted as a free hearing screening test to the public. Aside from detecting hearing loss, no studies have developed methods to differentiate and classify hearing loss further. Therefore, this study investigated more advanced DIN test methods that could serve this purpose. Study I evaluated if a combination of two DIN test paradigms (antiphasic and diotic) could accurately categorise hearing into (a) normal hearing (pure tone average [PTA] ≤ 25 dB HL), (b) bilateral sensorineural hearing loss (SNHL; PTA > 25 dB HL), or (c) unilateral SNHL (PTA > 25 dB HL in the poorer ear and ≥ 20 dB interaural PTA difference) or conductive hearing loss (CHL; air conduction PTA > 25 dB HL and ≥ 20 dB air-bone gap). After establishing normative antiphasic SRTs across a sample of 489 adults with varying types and degrees of hearing, 393 participants completed a second diotic DIN test. The antiphasic DIN test had sensitivity and specificity of 90% and 84% to detect hearing loss. Furthermore, the combined antiphasic and diotic DIN test approach with fixed SRT cut-offs could correctly categorize 75% of the sample. Using a fixed antiphasic and sloping diotic SRT cut-off (varying slope and offset) could increase classification to 79%. False-negative rates for both procedures were below 10%. Study II investigated a different approach to determine if CHL could be accurately distinguished from bilateral SNHL using a combination of pure tone audiometry and a diotic DIN test. An analyses of 122 adults with bilateral SNHL and 36 with CHL was conducted. Binomial logistic regression determined the effect of pure tone thresholds, SRT and age on the likelihood of having CHL or bilateral SNHL. A model including low-frequency PTA (0.5 & 1 kHz), diotic DIN SRT, and age had sensitivity and specificity of 97.2% and 93.4%, respectively, to distinguish CHL from bilateral SNHL. Instead of establishing a hearing loss type, Study III aimed to determine if a low-pass (LP) and high-pass (HP) speech filtering technique could estimate pure tone audiometry in separate low and high-frequency bands. Previous work has used LP filtered masking noise to increase the sensitivity of the DIN test to high-frequency hearing loss. However, this study filtered speech at 1.5 kHz to ensure minimal speech information presented above or below the filter cut-off frequency. Results indicated better test-retest reliability (Intraclass correlation coefficient [ICC] = 0.71; 95% confidence interval [CI] 0.52 to 0.82) of the HP DIN test than the LP DIN test (ICC = 0.39; 95% CI -0.01 to 0.63). The HP DIN SRT was more strongly correlated to all the PTA averages (four frequency, low-frequency and high-frequency) than the unfiltered, broadband (BB) or LP DIN test. Subsequently, the HP DIN test showed increased sensitivity and specificity to detect hearing loss in any PTA average, compared to the BB or LP DIN test. The LP DIN test had a weaker correlation to low-frequency thresholds than the BB DIN test. As a result, a combined LP and HP DIN test approach could not accurately predict an audiometric slope or configuration. For ears with normal hearing (PTA ≤ 15 dB HL), the HP DIN showed a stronger correlation (rs = 0.36) to extended high frequencies (8 to 16 kHz) than the BB DIN (rs = 0.26). As an implementation research approach, study IV investigated the global use and uptake, test characteristics and performance of an antiphasic DIN test as provided on the free World Health Organization smartphone hearing screening test (hearWHO). The data of 242 626 tests conducted by adults (> 18 years) conducted between February 2019 and May 2021 were evaluated. The test was completed in nearly every country globally (n = 179/195), with the greatest uptake seen in China and India. Uptake was most significant in the Western Pacific (32.9 %) and European (24.8 %) WHO regions. As expected, referral rates were typically higher for older age groups in most WHO regions, except for the African and Eastern Mediterranean regions, where overall hearWHO test uptake was lowest. There was a high uptake of tests (44%) by young adults under 30 years. The sequential antiphasic-diotic DIN test approach to classify hearing loss has the potential to optimise care pathways using remote and contactless testing by identifying unilateral SNHL and CHL as cases requiring medical referral. In contrast, bilateral SNHL cases could be referred directly to a hearing care professional or be served using non-traditional models. Furthermore, considering restrictions on traditional audiological assessments due to an infectious disease like COVID-19 and under-resourced settings, alternative methods that enable audiological care with minimal physical contact may reduce mortality and infection risk whilst optimising care pathways and resource allocation. This DIN test approach and the combined pure tone audiometry and diotic DIN test method could allow accurate detection of CHL without the use of bone conduction testing conducted in sound-proof booths. The DIN test could further sensitively discriminate hearing, especially occurring in high-frequencies when using HP speech filtered stimuli, and shows potential to detect early signs of hearing loss occurring in the extended high frequency (≥ 8 kHz) range. As an applied public health practice, the test reaches an important target audience of younger adults positioning it as an important measure for public health advocacy to prevent hearing loss due to unsafe listening practices. This study project provides empirical evidence that DIN test methods can support improved detection and classification of different hearing loss types. These advances contribute to growing research to optimise the DIN test efficiency and sensitivity as a screening and potential triaging tool. Furthermore, these classification methods can provide simple, applied solutions that support alternative service delivery models like over-the-counter or direct-to-consumer pathways.Thesis (DPhil (Communication Pathology: Audiology))--University of Pretoria, 2021.Skye FoundationSpeech-Language Pathology and AudiologyDPhil (Communication Pathology: Audiology)Unrestricte

Integrating Māori knowledge and cultural values into audiological research and hearing health services : an approach inspired by He Awa Whiria – a braided rivers framework.

In Aotearoa me Te Waipounamu/New Zealand, Māori are frequently underserved and excluded by hearing health services rooted in the dominant culture's values. Health workers often overlook Māori cultural values, leaving many Māori feeling alienated, whakamā (ashamed/embarrassed), and unsafe. A 'one-size-fits-all' approach to health service design and delivery has created systemic barriers to access that disproportionately affect Māori. Consequently, there are significant inequities in outcomes for Māori and greater unmet need relative to non-Māori. While the medical model has undeniable utility, there is considerable scope for the audiology profession to challenge the dominance of Western biomedical approaches to hearing healthcare and to broaden its thinking to deliver culturally appropriate services for Māori clients. This study explores how Māori knowledge and cultural values could be integrated into audiological research and mainstream audiology services. Inspired by He Awa Whiria – A Braided Rivers framework (Macfarlane et al., 2015), I suggest an approach that combines indigenous Māori and Western knowledge traditions. Further Māori-led research informed by kaupapa Māori principles is needed to evaluate this approach and how it may apply to hearing health services more broadly

Do informal caregivers of people with dementia mirror the cognitive deficits of their demented patients?:A pilot study

Recent research suggests that informal caregivers of people with dementia (ICs) experience more cognitive deficits than noncaregivers. The reason for this is not yet clear. Objective: to test the hypothesis that ICs ‘mirror' the cognitive deficits of the demented people they care for. Participants and methods: 105 adult ICs were asked to complete three neuropsychological tests: letter fluency, category fluency, and the logical memory test from the WMS-III. The ICs were grouped according to the diagnosis of their demented patients. One-sample ttests were conducted to investigate if the standardized mean scores (t-scores) of the ICs were different from normative data. A Bonferroni correction was used to correct for multiple comparisons. Results: 82 ICs cared for people with Alzheimer's dementia and 23 ICs cared for people with vascular dementia. Mean letter fluency score of the ICs of people with Alzheimer's dementia was significantly lower than the normative mean letter fluency score, p = .002. The other tests yielded no significant results. Conclusion: our data shows that ICs of Alzheimer patients have cognitive deficits on the letter fluency test. This test primarily measures executive functioning and it has been found to be sensitive to mild cognitive impairment in recent research. Our data tentatively suggests that ICs who care for Alzheimer patients also show signs of cognitive impairment but that it is too early to tell if this is cause for concern or not

Refinement and Normalisation of the University of Canterbury Auditory-Visual Matrix Sentence Test

Developed by O＇Beirne and Trounson (Trounson, 2012), the UC Auditory-Visual Matrix Sentence Test (UCAMST) is an auditory-visual speech test in NZ English where sentences are assembled from 50 words arranged into 5 columns (name, verb, quantity, adjective, object). Generation of sentence materials involved cutting and re-assembling 100 naturally spoken ‟original” sentences to create a large repertoire of 100,000 unique ‟synthesised” sentences. The process of synthesising sentences from video fragments resulted in occasional artifactual image jerks (‟judders”)‒quantified by an unusually large change in the ‟pixel difference value” of consecutive frames‒at the edited transitions between video fragments. To preserve the naturalness of materials, Study 1 aimed to select transitions with the least ‟noticeable” judders. Normal-hearing participants (n = 18) assigned a 10-point noticeability rating score to 100 sentences comprising unedited ‟no judder” sentences (n = 28), and ‟synthesised” sentences (n = 72) that varied in the severity (i.e. pixel difference value), number, and position of judders. The judders were found to be significantly noticeable compared to no judder controls, and based on mean rating score, 2,494 sentences with ‟minimal noticeable judder” were included in the auditory-visual UCAMST. Follow-on work should establish equivalent lists using these sentences. The average pixel difference value was found to be a significant predictor of rating score, therefore may be used as a guide in future development of auditory-visual speech tests assembled from video fragments. The aim of Study 2 was to normalise the auditory-alone UCAMST to make each audio fragment equally intelligible in noise. In Part I, individuals with normal hearing (n = 17) assessed 400 sentences containing each file fragment presented at four different SNRs (-18.5, -15, -11.5, and -8 dB) in both constant speech-shaped noise (n = 9) and six-talker babble (n = 8). An intelligibility function was fitted to word-specific data, and the midpoint (Lmid, intelligibility at 50%) of each function was adjusted to equal the mean pre-normalisation midpoint across fragments. In Part II, 30 lists of 20 sentences were generated with relatively homogeneous frequency of matrix word use. The predicted parameters in constant noise (Lmid = 14.0 dB SNR; slope = 13.9%/dB ± 0.0%/dB) are comparable with published equivalents. The babble noise condition was, conversely, less sensitive (Lmid = 14.9 dB SNR; slope = 10.3%/dB ± 0.1%/dB), possibly due to a smaller sample size (n = 8). Overall, this research constituted an important first step in establishing the UCAMST as a reliable measure of speech recognition; follow-on work will validate the normalisation procedure carried out in this project