Development of the Mandarin Digit-in-Noise Test and Examination of the Effect of the Number of Digits Used in the Test.

OBJECTIVES: The study aimed to develop and validate the Mandarin digit-in-noise (DIN) test using four digit (i.e., two-, three-, four-, and five-digit) sequences. Test-retest reliability and criterion validity were evaluated. How the number of digits affected the results was examined. The research might lead to more informed choice of DIN tests for populations with specific cognitive needs such as memory impairment. DESIGN: The International Collegium of Rehabilitative Audiology guideline for developing the DIN was adapted to create test materials. The test-retest reliability and psychometric function of each digit sequence were determined among young normal-hearing adults. The criterion validity of each digit sequence was determined by comparing the measured performance of older adult hearing aid users with that obtained from two other well-established sentence-in-noise tests: the Mandarin hearing-in-noise test and the Mandarin Chinese matrix test. The relation between the speech reception thresholds (SRTs) of each digit sequence of the DIN test and working memory capacity measured using the digit span test and the reading span test were explored among older adult hearing aid users. Together, the study sample consisted of 54 young normal-hearing adults and 56 older adult hearing aid users. RESULTS: The slopes associated with the two-, three-, four-, and five-digit DIN test were 16.58, 18.79, 20.42, and 21.09 %/dB, respectively, and the mean SRTs were -11.11, -10.99, -10.56, and -10.02 dB SNR, respectively. Test-retest SRTs did not differ by more than 0.74 dB across all digit sequences, suggesting good test-retest reliability. Spearman rank-order correlation coefficients between SRTs obtained using the DIN across the four digit (i.e., two-, three-, four-, and five-digit) sequences and the two sentence-in-noise tests were uniformly high ( rs = 0.9) across all participants, when data from all participants were considered. Results from the digit span test and reading span test correlated significantly with the results of the five-digit sequences ( rs = -0.37 and -0.42, respectively) but not with the results of the two-, three-, and four-digit sequences among older hearing aid users. CONCLUSIONS: While the three-digit sequence was found to be appropriate for clinical use for assessment of auditory perception, the two-digit sequence could be used for hearing screening. The five-digit sequence could be difficult for older hearing aid users, and with its SRT related to working memory capacity, its use in the evaluation of speech perception should be investigated further. The Mandarin DIN test was found to be reliable, and the findings are in line with SRTs obtained using standardized sentence tests, suggesting good criterion validity.

Deep Learning Models for Predicting Hearing Thresholds Based on Swept-Tone Stimulus-Frequency Otoacoustic Emissions.

OBJECTIVES: This study aims to develop deep learning (DL) models for the quantitative prediction of hearing thresholds based on stimulus-frequency otoacoustic emissions (SFOAEs) evoked by swept tones. DESIGN: A total of 174 ears with normal hearing and 388 ears with sensorineural hearing loss were studied. SFOAEs in the 0.3 to 4.3 kHz frequency range were recorded using linearly swept tones at a rate of 2 Hz/msec, with stimulus level changing from 40 to 60 dB SPL in 10 dB steps. Four DL models were used to predict hearing thresholds at octave frequencies from 0.5 to 4 kHz. The models-a conventional convolutional neural network (CNN), a hybrid CNN-k-nearest neighbor (KNN), a hybrid CNN-support vector machine (SVM), and a hybrid CNN-random forest (RF)-were individually built for each frequency. The input to the DL models was the measured raw SFOAE amplitude spectra and their corresponding signal to noise ratio spectra. All DL models shared a CNN-based feature self-extractor. They differed in that the conventional CNN utilized a fully connected layer to make the final regression decision, whereas the hybrid CNN-KNN, CNN-SVM, and CNN-RF models were designed by replacing the last fully connected layer of CNN model with a traditional machine learning (ML) regressor, that is, KNN, SVM, and RF, respectively. The model performance was evaluated using mean absolute error and SE averaged over 20 repetitions of 5 × 5 fold nested cross-validation. The performance of the proposed DL models was compared with two types of traditional ML models. RESULTS: The proposed SFOAE-based DL models resulted in an optimal mean absolute error of 5.98, 5.22, 5.51, and 6.06 dB at 0.5, 1, 2, and 4 kHz, respectively, superior to that obtained by the traditional ML models. The produced SEs were 8.55, 7.27, 7.58, and 7.95 dB at 0.5, 1, 2, and 4 kHz, respectively. All the DL models outperformed any of the traditional ML models. CONCLUSIONS: The proposed swept-tone SFOAE-based DL models were capable of quantitatively predicting hearing thresholds with satisfactory performance. With DL techniques, the underlying relationship between SFOAEs and hearing thresholds at disparate frequencies was explored and captured, potentially improving the diagnostic value of SFOAEs.

Assessment of Interaural Attenuation in Infants and Young Children Using Bone-Conducted Auditory Brainstem Response.

OBJECTIVES: In hearing assessment, the term interaural attenuation (IAA) is used to quantify the reduction in test signal intensity as it crosses from the side of the test ear to the nontest ear. In the auditory brainstem response (ABR) testing of infants and young children, the size of the IAA of bone-conducted (BC) stimuli is essential for the appropriate use of masking, which is needed for the accurate measurement of BC ABR thresholds. This study aimed to assess the IAA for BC ABR testing using 0.5 to 4 kHz narrowband (NB) CE-chirp LS stimuli in infants and toddlers with normal hearing from birth to three years of age and to examine the effects of age and frequency on IAA. DESIGN: A total of 55 infants and toddlers with normal hearing participated in the study. They were categorized into three age groups: the young group (n = 31, infants from birth to 3 mo), middle-aged group (n = 13, infants aged 3-12 mo), and older group (n = 11, toddlers aged 12-36 mo). The participants underwent BC ABR threshold measurements for NB CE-chirp LS stimuli at 0.5 to 4 kHz. For each participant, one ear was randomly defined as the "test ear" and the other as the "nontest ear." BC ABR thresholds were measured under two conditions. In both conditions, traces were recorded from the channel ipsilateral to the test ear, whereas masking was delivered to the nontest ear. In condition A, the bone oscillator was placed on the mastoid of the test ear, whereas in condition B, the bone oscillator was placed on the mastoid contralateral to the test ear. The difference between the thresholds obtained under conditions A and B was calculated to assess IAA. RESULTS: The means of IAA (and range) in the young age group for the frequencies 0.5, 1, 2, and 4 kHz were 5.38 (0-15) dB, 11.67 (0-30) dB, 21.15 (10-40) dB, and 23.53 (15-35) dB, respectively. Significant effects were observed for both age and frequency on BC IAA. BC IAA levels decreased with age from birth to 36 mo. In all age groups, smaller values were observed at lower frequencies and increased values were observed at higher frequencies. CONCLUSIONS: BC IAA levels were both age and frequency dependent. The study found that the BC IAA values for lower stimulus frequencies were smaller than previously assumed, even in infants younger than 3 mo. These results suggest that masking should be applied in BC ABR threshold assessments for NB CE-chirp LS stimuli at 0.5, 1, and 2 kHz, even in young infants. Masking may not be necessary for testing at 4 kHz if a clear response is obtained at 15 dB normal-hearing level (nHL) in infants younger than 3 mo.

Neonatal hearing screening - does failure in TEOAE screening matter when the AABR test is passed?

PURPOSE: Newborns who fail the transient evoked otoacoustic emissions (TEOAE) but pass the automatic auditory brainstem response (AABR) in universal newborn hearing screening (UNHS), frequently have no further diagnostic test or follow-up. The present study aimed to investigate whether hearing loss might be missed by ignoring neonatal TEOAE failure in the presence of normal AABR. METHODS: A retrospective analysis was conducted in newborns presenting between 2017 and 2021 to a tertiary referral centre due to failure in the initial UNHS. The main focus was on infants who failed TEOAE tests, but passed AABR screening. The clinical characteristics and audiometric outcomes were analysed and compared with those of other neonates. RESULTS: Among 1,095 referred newborns, 253 (23%) failed TEOAE despite passing AABR screening. Of the 253 affected infants, 154 returned for follow-up. At 1-year follow-up, 46 (28%) achieved normal audiometric results. 32 (21%) infants had permanent hearing loss (HL) confirmed by diagnostic ABR, 58 (38%) infants had HL solely due to middle ear effusion (MEE), and for 18 (12%) infants HL was suspected without further differentiation. The majority of permanent HL was mild (78% mild vs. 13% moderate vs. 9% profound). The rate of spontaneous MEE clearance was rather low (29%) leading to early surgical intervention in 36 children. The profile of the risk factors for hearing impairment was similar to that of newborns with failure in both, TEOAE and AABR; however, there was a stronger association between the presence of risk factors and the incidence of HL (relative risk 1.55 vs. 1.06; odds ratio 3.61 vs. 1.80). CONCLUSION: In newborns, the discordance between a "refer" in TEOAE and a "pass" in AABR screening is associated with a substantial prevalence of hearing impairment at follow-up, especially in the presence of risk factors.

Hearing loss and cognition: A protocol for ensuring speech understanding before neurocognitive assessment.

INTRODUCTION: Many neurocognitive evaluations involve auditory stimuli, yet there are no standard testing guidelines for individuals with hearing loss. The ensuring speech understanding (ESU) test was developed to confirm speech understanding and determine whether hearing accommodations are necessary for neurocognitive testing. METHODS: Hearing was assessed using audiometry. The probability of ESU test failure by hearing status was estimated in 2679 participants (mean age: 81.4 ± 4.6 years) using multivariate logistic regression. RESULTS: Only 2.2% (N = 58) of participants failed the ESU test. The probability of failure increased with hearing loss severity; similar results were observed for those with and without mild cognitive impairment or dementia. DISCUSSION: The ESU test is appropriate for individuals who have variable degrees of hearing loss and cognitive function. This test can be used prior to neurocognitive testing to help reduce the risk of hearing loss and compromised auditory access to speech stimuli causing poorer performance on neurocognitive evaluation.

Reaching to Sounds Improves Spatial Hearing in Bilateral Cochlear Implant Users.

OBJECTIVES: We assessed if spatial hearing training improves sound localization in bilateral cochlear implant (BCI) users and whether its benefits can generalize to untrained sound localization tasks. DESIGN: In 20 BCI users, we assessed the effects of two training procedures (spatial versus nonspatial control training) on two different tasks performed before and after training (head-pointing to sound and audiovisual attention orienting). In the spatial training, participants identified sound position by reaching toward the sound sources with their hand. In the nonspatial training, comparable reaching movements served to identify sound amplitude modulations. A crossover randomized design allowed comparison of training procedures within the same participants. Spontaneous head movements while listening to the sounds were allowed and tracked to correlate them with localization performance. RESULTS: During spatial training, BCI users reduced their sound localization errors in azimuth and adapted their spontaneous head movements as a function of sound eccentricity. These effects generalized to the head-pointing sound localization task, as revealed by greater reduction of sound localization error in azimuth and more accurate first head-orienting response, as compared to the control nonspatial training. BCI users benefited from auditory spatial cues for orienting visual attention, but the spatial training did not enhance this multisensory attention ability. CONCLUSIONS: Sound localization in BCI users improves with spatial reaching-to-sound training, with benefits to a nontrained sound localization task. These findings pave the way to novel rehabilitation procedures in clinical contexts.

Is intrauterine exposure to COVID-19 infection a risk factor for infant hearing loss?

PURPOSE: To determine whether exposure to intrauterine COVID-19 infection causes congenital or late-onset hearing loss in infants. MATERIAL AND METHOD: The hearing screening results of infants born in a tertiary hospital between March 2020 and April 2022 with and without a history of intrauterine exposure to COVID-19 infection (36 infants each) were retrospectively analyzed within one month after birth in all infants and additionally at six months after intrauterine COVID-19 infection exposure in the study group. The automated auditory brainstem response (AABR) test was used for the hearing evaluation. RESULTS: The polymerase chain reaction test was negative in study group exposed to intrauterine COVID-19 infection. The number of infants admitted to the intensive care unit (ICU), and the length of ICU stay were significantly higher in this group (p < 0.01). Six infants (16.6 %) in the study group failed the first AABR test bilaterally, but five of these infants passed the second AABR test. A bilateral severe sensorineural hearing loss was detected in one infant (2.77 %). All the infants in the study group underwent the AABR test again at six months, and all infants, except this infant, passed the test. In the control group, five infants (13.88 %) failed the first AABR test bilaterally, but they all passed the second test. CONCLUSIONS: Exposure to COVID-19 infection in the intrauterine period does not cause congenital or late-onset hearing loss (within six months) in infants; therefore, gestational COVID-19 infection is not a risk factor for infant hearing loss.

Training spatial hearing in unilateral cochlear implant users through reaching to sounds in virtual reality.

BACKGROUND AND PURPOSE: Use of unilateral cochlear implant (UCI) is associated with limited spatial hearing skills. Evidence that training these abilities in UCI user is possible remains limited. In this study, we assessed whether a Spatial training based on hand-reaching to sounds performed in virtual reality improves spatial hearing abilities in UCI users METHODS: Using a crossover randomized clinical trial, we compared the effects of a Spatial training protocol with those of a Non-Spatial control training. We tested 17 UCI users in a head-pointing to sound task and in an audio-visual attention orienting task, before and after each training.
Study is recorded in clinicaltrials.gov (NCT04183348). RESULTS: During the Spatial VR training, sound localization errors in azimuth decreased. Moreover, when comparing head-pointing to sounds before vs. after training, localization errors decreased after the Spatial more than the control training. No training effects emerged in the audio-visual attention orienting task. CONCLUSIONS: Our results showed that sound localization in UCI users improves during a Spatial training, with benefits that extend also to a non-trained sound localization task (generalization). These findings have potentials for novel rehabilitation procedures in clinical contexts.

Model-based prediction of otoacoustic emission level, noise level, and signal-to-noise ratio during time-synchronous averaging.

Although averaging is effective in reducing noise, its efficiency rapidly decreases beyond several hundred averages. Depending on environmental and patient noise levels, several hundred averages may be insufficient for informed clinical decision making. The predictable nature of the otoacoustic emission (OAE) and noise during time-synchronous averaging implicates the use of predictive modeling as an alternative to increased averaging when noise is high. Click-evoked OAEs were measured in 98, normal-hearing subjects. Average OAE and noise levels were calculated for subsets of the total number of averages and then fit using variants of a power function. The accuracy of the models was quantified as the difference between the measured value and model output. Models were used to predict the OAE signal-to-noise ratio (SNR) for a criterion noise level. Based on predictions, the OAE was categorized as present or absent. Model-based decisions were compared to decisions from direct measurements. Model accuracy improved as the number of averages (and SNR in the case of OAEs) from which the model was derived increased. Model-based classifications permitted correct categorization of the OAE status from fewer averages than measurement-based classifications. Furthermore, model-based predictions resulted in fewer false positives (i.e., absent OAE despite normal hearing).

Dolphins reduce hearing sensitivity in anticipation of repetitive impulsive noise exposures.

The auditory steady-state response (ASSR) was continuously measured in two bottlenose dolphins during impulse noise exposures to determine whether observed head movements coincided with actual changes to auditory system sensitivity. Impulses were generated by a seismic air gun at a fixed inter-pulse interval of 10 s. ASSR amplitudes were extracted from the instantaneous electroencephalogram using coherent averaging within a sliding analysis window. A decline in ASSR amplitude was seen during the time interval between air gun impulses, followed by an elevation in ASSR amplitude immediately after each impulse. Similar patterns were not observed during control trials where air gun impulses were not generated. The results suggest that the dolphins learned the timing of the impulse noise sequences and lowered their hearing sensitivity before each impulse, presumably to lessen the auditory effects of the noise. The specific mechanisms responsible for the observed effects are at present unknown.

Cost-effectiveness analysis on implementing newborn hearing screening programmes in a low- to middle-income country.

OBJECTIVE: To analyse the cost-effectiveness (CE) of implementing different newborn hearing screening protocols in a low- to middle-income country. DESIGN: A decision analytical model with a 78-year time horizon. STUDY SAMPLE: Direct medical, direct non-medical and indirect costs were collected from 126 subjects in southern Thailand. Various protocols involving universal newborn hearing screening (UNHS) and targeted newborn hearing screening (TNHS), using two technologies, namely automated otoacoustic emissions (aOAEs) and automated auditory brainstem responses (aABRs), were evaluated. Incremental cost-effectiveness ratios (ICERs) were calculated for all protocols in United States dollars (US$)/quality-adjusted life year (QALY) gained. Also, probabilistic sensitivity analyses with 1000 trials for each specific protocol were performed. RESULTS: The ICERs of UNHS with aOAE, UNHS with aABR, TNHS with aABR and UNHS with optimised baseline parameters were 3702, 3545, 1545 and 2483 US$/QALY gained, respectively. With the CE threshold of 5000 US$/QALY gained, the chances of ICERs to be cost-effective for UNHS with aOAE, UNHS with aABR, TNHS with aABR and UNHS with optimised baseline parameters were 72, 77, 93 and 94%, respectively. CONCLUSIONS: All screening protocols were considered as cost-effective, and a very high chance of being cost-effective for UNHS could be achieved when certain baseline parameters were optimised.

Neonatal bacterial meningitis: hearing screening and audiological monitoring outcomes.

OBJECTIVE: This study reviewed the outcomes of universal newborn hearing screening (UNHS) and ongoing hearing monitoring in children following recovery from neonatal bacterial meningitis to determine (a) whether screening may be a suitable alternative to diagnostic audiology for detecting permanent childhood hearing loss (PCHL) and (b) whether infants who pass UNHS should be monitored throughout childhood. DESIGN: Retrospective analysis of a UNHS database. STUDY SAMPLE: Data were extracted from the state-wide UNHS database for all children born in Queensland Australia between 1 September 2004 and 30 June 2020 with the risk factor of bacterial meningitis (in isolation or in combination with other risk factors) identified at the time of the UNHS. This cohort included 231 children. RESULTS: Results showed that all post-meningitic infants diagnosed with PCHL had a refer result on the UNHS or were medically excluded from screening. Additionally, no cases of PCHL were identified through the targeted surveillance program following a pass result on UNHS. CONCLUSIONS: UNHS may be sufficient to detect PCHL in post-meningitic neonates and routine audiological monitoring may not be required for children who pass the screen.

[Automatic hearing screening for better monitoring of hearing health using the example of the German armed forces]. / Automatisiertes Hörscreening zur verbesserten Überwachung der Hörgesundheit am Beispiel der Bundeswehr.

In the present study, the concept of a systematic automated screening of temporary soldiers was evaluated based on the example of the ENT Department of the Bundeswehr Central Hospital Koblenz. From 2014 to 2017, anonymized data of 169 individuals were collected from the setting of the Bundeswehr Central Hospital. Included in the data are results from measurements with automated pure-tone audiometry (APTA; e.g., [3]), from measurements with the digit triple test for determination of the speech discrimination threshold in noise (e.g., [20]), and from interviews with questionnaires (Hearing-Dependent Daily Activities [HDDA], e.g., [14]; HearCom questionnaire, e.g., [15]). There was an initial publication from this project evaluating the questionnaires in terms of their suitability for detecting hearing loss [14]. In the following (from March 2015), only the HDDA, which was described as more sensitive, was used for measurements at the hearing screening measurement station. A complete run with the three procedures took approximately 22 min. Approximately 17% of the examined participants had abnormal findings in at least one of the procedures at the screening station. The results of the respective methods taken together detect more than any method alone and can be assumed to be complementary. Deviations between APTA with level monitor and manual tone audiometry were within the measurement accuracy. In the range between 1 and 4 kHz, hearing thresholds are somewhat underestimated with APTA. The threshold for the HDDA questionnaire with an HDDA sum ≥ 19 was confirmed. Automated hearing screening offers a good opportunity to check hearing ability on a regular basis in a standardized and reliable manner, while keeping personnel requirements low.

Establishing transducers-dependent sensorineural acuity level normative data among young Malaysian adults.

INTRODUCTION: The sensorineural acuity level (SAL) test was developed as an alternative assessment to estimate bone conduction (BC) thresholds in cases where masking problems occur in pure tone audiometry (PTA). Nevertheless, prior to its clinical application, the respective SAL normative data must be made available. As such, the present study was carried out to establish SAL normative data using an insert earphone and two different commercially available bone transducers. Additionally, to determine the effect of earphone type on SAL test results, it was also of interest to compare the present study's findings with those of a previous study (that used a headphone to derive SAL normative data). MATERIALS AND METHODS: In this repeated-measures study, 40 Malaysian adults (aged 19-26 years) with normal hearing bilaterally (based on PTA results) were enrolled. They then underwent the SAL test based on the recommended protocol by Jerger and Tillman (1960). The SAL normative data for each ear were obtained by calculating the differences between air conduction (AC) thresholds in quiet and AC thresholds in noise by means of insert earphone, B71 and B81 bone vibrators. RESULTS: The SAL normative values were comparable between the ears (p > 0.05), and the data were pooled for subsequent analyses (n = 80 ears). Relative to B81 bone transducer, B71 bone vibrator produced statistically higher SAL normative data at all frequencies (p < 0.05). The SAL normative values established by the present study were statistically lower than those of the previous study (that utilised headphones) at most of frequencies tested (p < 0.05). CONCLUSIONS: The SAL normative data produced by the two bone vibrators were significantly different. The SAL normative values were also affected by the type of earphone used. While conducting the SAL test on Malaysian patients, the information provided by this study can be useful to guide the respective clinicians in choosing the appropriate normative data.

A regional-based newborn hearing screening program: the Emilia-Romagna model after ten years of legislation.

Background: Hearing loss, occurring in 1-3/1,000 newborns in the well-babies population, is one of the most common congenital diseases, and hearing screening at birth still represents the only means for its early detection. Since 2011 the Emilia Romagna Regional Health Agency has recommended Newborn Hearing Screening for all babies at its birth points and for newborns moving to the region. The aims of this study are to analyze the results of this regional-based Newborn Hearing Screening program and to discuss the impact of the legislative endorsement on the organization. Material and methods: This is an observational retrospective chart study. The recordings of well-babies and babies at Neonatal Intensive Care Units were collected during the period from January 1st 2015 to December 31st 2020. The following data were included: Newborn Hearing Screening coverage, percentage of refer at otoacoustic emissions, prevalence and entity of hearing loss, unilateral/bilateral rate, presence of audiological risk factors. Results: More than 99% of a total of 198,396 newborns underwent the Newborn Hearing Screening test during the period January 1st 2015 to December 31st 2020, with a coverage ranging between 99.6% and 99.9%. Overall, the percentage of confirmed hearing loss cases was about 17-30 % of refer cases, 745 children received a diagnosis of hearing loss (prevalence 3.7/1,000). Considering profound hearing loss cases, these represent 13% of bilateral hearing loss. Conclusion: A regional-based Newborn Hearing Screening program is valuable and cost-effective. In our experience, the centralization of the data system and of the data control is crucial in order to implement its efficiency and effectiveness. Healthcare policies, tracking systems and public awareness are decisive for a successful programme implementation.

[Results of the audit of the first stage newborn hearing screening in St. Petersburg]. / Rezul'taty audita pervogo etapa audiologicheskogo skrininga novorozhdennykh v Sankt-Peterburge.

OBJECTIVE: Analysis of the first stage of universal newborn hearing screening in St. Petersburg and increasing its effectiveness. RESULTS: In result of the audit, it was found that screening performs in all maternity wards, children's hospitals and at the majority of pediatric clinics. Meanwhile only 14% of institutions meet criteria of good practice in providing screening. In other clinics improving the procedure of screening is needed: equipment update and calibration, correction of the method and conditions of examination, results documenting, etc. The set of activities for increasing the effectiveness of newborn hearing screening is proposed. The work which carried out with institutions during and after audit allowed to reach 100% involving clinics in screening system in 6 months. Due to information support of institutions coverage of newborns by the first stage of screening increased on 8.5% (matched to target) and the number of referred children who come to the second stage of screening increased on 18%. Results suggest that the audit of the first stage of newborn hearing screening by the district pediatric audiological centers is an effective tool for finding problems in the screening system and its solving.

Threshold Equalizing Noise Test Reveals Suprathreshold Loss of Hearing Function, Even in the "Normal" Audiogram Range.

OBJECTIVES: The threshold equalizing noise (TEN(HL)) is a clinically administered test to detect cochlear "dead regions" (i.e., regions of loss of inner hair cell [IHC] connectivity), using a "pass/fail" criterion based on the degree of elevation of a masked threshold in a tone-detection task. With sensorineural hearing loss, some elevation of the masked threshold is commonly observed but usually insufficient to create a "fail" diagnosis. The experiment reported here investigated whether the gray area between pass and fail contained information that correlated with factors such as age or cumulative high-level noise exposure (>100 dBA sound pressure levels), possibly indicative of damage to cochlear structures other than the more commonly implicated outer hair cells. DESIGN: One hundred and twelve participants (71 female) who underwent audiometric screening for a sensorineural hearing loss, classified as either normal or mild, were recruited. Their age range was 32 to 74 years. They were administered the TEN test at four frequencies, 0.75, 1, 3, and 4 kHz, and at two sensation levels, 12 and 24 dB above their pure-tone absolute threshold at each frequency. The test frequencies were chosen to lie either distinctly away from, or within, the 2 to 6 kHz region where noise-induced hearing loss is first clinically observed as a notch in the audiogram. Cumulative noise exposure was assessed by the Noise Exposure Structured Interview (NESI). Elements of the NESI also permitted participant stratification by music experience. RESULTS: Across all frequencies and testing levels, a strong positive correlation was observed between elevation of TEN threshold and absolute threshold. These correlations were little-changed even after noise exposure and music experience were factored out. The correlations were observed even within the range of "normal" hearing (absolute thresholds ≤15 dB HL). CONCLUSIONS: Using a clinical test, sensorineural hearing deficits were observable even within the range of clinically "normal" hearing. Results from the TEN test residing between "pass" and "fail" are dominated by processes not related to IHCs. The TEN test for IHC-related function should therefore only be considered for its originally designed function, to generate a binary decision, either pass or fail.

Diotic and Antiphasic Digits-in-noise Testing as a Hearing Screening and Triage Tool to Classify Type of Hearing Loss.

OBJECTIVES: The digits-in-noise test (DIN) is a popular self-test measure that has traditionally been used to screen for hearing loss by providing either a pass or refer result. Standard approaches either tested each ear monaurally or used a binaural diotic version where identical digits and noise were presented simultaneously to both ears. Recently, a dichotic, antiphasic version was developed, increasing sensitivity of the DIN to unilateral or asymmetric sensorineural hearing loss (SNHL) and conductive hearing loss (CHL). The purpose of this study was to determine predictors and normative ranges of the antiphasic and diotic DIN and to determine if a combination of diotic and antiphasic DIN could accurately categorize hearing into (1) normal, (2) bilateral SNHL, or (3) unilateral SNHL or CHL. DESIGN: The analytical sample consisted of 489 participants between the ages of 18 and 92 years with varying types, symmetry, and degrees of hearing loss. Degree and type of hearing loss were determined based on standard clinical four-frequency (0.5-4 kHz) pure-tone air and bone conduction threshold averages. The sample consisted of bilateral normal hearing (n = 293), bilateral SNHL (n = 172), unilateral SNHL (n = 42), and CHL (n = 32). All participants (n = 489) first completed an antiphasic DIN (digit stimuli 180° out-of-phase between ears), while 393 of the sample also completed a diotic DIN. Two procedures were assessed for their ability to categorize hearing into one of the three hearing groups. The first used a fixed antiphasic cutoff combined with a cutoff formed by a linear combination of antiphasic and diotic speech recognition threshold (SRT) or binaural intelligibility-level difference. RESULTS: Poorer ear pure-tone average was the strongest predictor of antiphasic DIN score, whereas better ear pure-tone average explained more of the variance in diotic SRT. The antiphasic DIN sensitivity and specificity was 90% and 84%, respectively, for detecting hearing loss, with outstanding area under the receiver operating characteristics values exceeding 0.93 to identify hearing loss in the poorer ear. The first fixed SRT cutoff procedure could categorize 75% of all participants correctly, while the second procedure increased correct categorization to 79%. False negative rates for both procedures were below 10%. CONCLUSIONS: A sequential antiphasic and diotic DIN could categorize hearing to a reasonable degree into three groups of (1) normal hearing; (2) bilateral SNHL; and (3) unilateral asymmetric SNHL or CHL. This type of approach could optimize 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 an audiologist, or nontraditional models like OTC hearing aids.

A systematic review of newborn and childhood hearing screening around the world: comparison and quality assessment of guidelines.

BACKGROUND: This study aimed to assess the quality of global guidelines or consensus statements for newborn and childhood hearing screening, as well as to compare various guidelines between other countries and China. METHODS: A PROSPERO registered systematic review (number CRD42021242198) was conducted. Multiple electronic databases and government websites including PubMed, EMBASE, Web of Science, CENTRAL, Cochrane Library, and BMJ Best Practice were searched from inception until May 2021. The latest national and international guidelines, consensus statements, technical specifications, and recommendations regarding newborn or childhood hearing screening that were published in Chinese or English medical journals or elsewhere with the full version available online. The following information was extracted independently by two reviewers for comparative analysis: titles, authors, publication year, country, the source organization, and main key recommendations using systems for assigning the level of evidence and strength of recommendations. The quality of the guidelines was assessed by three independent reviewers using the Appraisal of Guidelines for Research and Evaluation, 2nd edition. Intraclass correlation coefficients (ICCs) were calculated to assess among-reviewer agreement. RESULTS: We assessed 15 newborn and 6 childhood hearing screening guidelines, respectively. Most newborn guidelines recommend the 1-3-6 guidelines and pre-discharge screening; however, the specific screening times differ. 93.33% of newborn hearing guidelines recommend "primary screening-re-screening-diagnosis-intervention" for well-babies while 73.33% of the guidelines recommend "initial screening-diagnosis-intervention" for newborns in neonatal intensive care unit (NICU); 33.33% of the newborn hearing guidelines recommended initial screening coverage of > 95% while 46.66% did not mention it. Further, 26.66% of the newborn hearing guidelines recommended a referral rate to diagnosis within 4% while 60% did not mention it. Regarding childhood hearing screening guidelines, the screening populations differed across guidelines (age range: 0-9 years); most guidelines recommend pediatric hearing screening for all preschoolers. Only 50% of the guidelines specify screening and re-screening techniques, including pure-tone hearing screening, OAE, tympanometry, and others. The "Clarity of Presentation" domain achieved the highest mean score, and the lowest was "Editorial Independence" both in newborn and childhood guidelines. Overall score of newborn hearing screening guidelines ranged from 3 (2018 Europe) to 7 (2019 America), with an average score of 5.33. Average score of childhood hearing screening guidelines was 4.78, with the score ranging from 4 (2017 England, 2012 Europe, 2016 WHO) to 6.67 (2011 America). ICC analysis revealed excellent agreement across 21 guidelines (> 0.75). CONCLUSIONS: These findings indicated newborn hearing screening guidelines had superior quality over childhood ones. Comparative analysis suggested that recommendations of the Chinese newborn and pediatric hearing screening protocols are consistent with the mainstream international opinion. Moreover, this analysis demonstrated that "Editorial Independence" and "Stakeholder Involvement" have the greatest opportunities for improvement. These results may help to advance the quality of hearing screening guidelines in clinical practice and guide evidence-based updates.

Prevalence and characteristics of hearing and vision loss in preschool children from low income South African communities: results of a screening program of 10,390 children.

BACKGROUND: The majority of children with sensory impairments live in low- and middle-income countries. More studies of hearing and vision impairment prevalence are needed, in order to generate more accurate estimates of trends in sensory impairments. This study aimed to estimate the prevalence and describe the characteristics of hearing and vision loss among preschool children (4-7 years) in an underserved South African community following community-based mobile health (mHealth) supported hearing and vision services. METHODS: A screening program of sensory impairments was undertaken of children attending preschools in the communities of Khayelitsha and Mitchell's Plain, Cape Town, from September 2017 until June 2019. Hearing and vision screening were done by trained community health workers using mHealth technology. Children who failed hearing and vision screening were seen for follow-up assessments at their preschools. Follow-up assessments were conducted using smartphones that host point-of-care validated and calibrated hearing and vision testing applications (hearTest app, hearX Group, South Africa and PeekAcuity app, Peek Vision, United Kingdom). Descriptive statistical analysis and logistic regression analysis were conducted after extracting data from a secure cloud-based server (mHealth Studio, hearX Group) to Microsoft Excel (2016). RESULTS: A total of 10,390 children were screened at 298 preschools over 22 months. Of the children screened, 5.6 and 4.4% of children failed hearing and vision screening respectively. Community-based follow-up hearing tests were done at the preschools on 88.5% (514) of children of whom 240 children (54.2% female) presented with hearing loss. A preschool-based follow-up vision test was done on 400 children (88.1%). A total of 232 children (46.1% female) had a vision impairment, and a further 32 children passed the test but had obvious signs of ocular morbidity. Logistic regression analysis found that age was a significant predictor of vision loss (p < 0.05), but not for hearing loss (p = 0.06). Gender was not a significant predictor of hearing (p = 0.22) or vision loss (p = 0.20). CONCLUSIONS: Hearing loss is prevalent in at least 22 per 1000 and vision loss in at least 23 per 1000 preschool children in an underserved South African community. Timely identification of sensory losses can be facilitated through community-based hearing and vision services supported by mHealth technology.