Smartphone-Facilitated In-Situ Hearing Aid Audiometry for Community-Based Hearing Testing.

OBJECTIVES: Hearing loss prevalence is increasing, with an estimated 2.5 billion people affected globally by 2050. Scalable service delivery models using innovative technologies and task-shifting are World Health Organization priorities to improve access to hearing care, particularly in low- and middle-income countries. Smartphone-facilitated audiometry in the community using hearing aids covered by noise-attenuating ear cups ("in-situ") could support more accessible hearing care when provided by less trained individuals such as community health workers (CHWs). This study aimed to determine the validity of this method for potential hearing aid fitting. Study objectives included determining the maximum permissible ambient noise level (MPANL), inter-device reliability, clinical threshold accuracy, reliability, and performance in real-world settings. DESIGN: Experiment 1: 15 normal-hearing adult participants were evaluated to determine MPANLs for circumaural Peltor 3M earcups covering Lexie Lumen hearing aids with smartphone-facilitated in-situ audiometry. MPANLs were calculated by measuring the difference in attenuation between thresholds obtained with standard headphones and in-situ hearing aids. Experiment 2: Pure-tone frequency and intensity output of 14 same-model Lexie Lumen hearing aids were measured to determine inter-device reliability. Pure-tone stimuli were measured and analyzed to determine sound pressure levels in decibels and pure-tone frequency when connected to a test box 2cc coupler. Experiment 3: 85 adult participants were tested in a sound booth to determine the accuracy of automated in-situ pure-tone audiometry (PTA) compared to clinical PTA (500, 1000, 2000, 3000, 4000, 6000 Hz) facilitated by an audiologist. The first 39 participants were tested twice to determine test-retest reliability. Experiment 4: In a community setting, 144 adult participants were tested with automated in-situ audiometry facilitated by CHWs using a smartphone app. These participants were subsequently tested with automated mobile PTA (500, 1000, 2000, 4000 Hz). An additional 44 participants were tested twice to determine test-retest reliability. RESULTS: Experiment 1: MPANLs of the Peltor 3M earcup-covered hearing aids were higher than standard headphones across all frequencies, ranging from 24 to 47.3 dB SPL. Experiment 2: Inter-device performance reliability was high, with all inter-device differences across all intensities and frequencies less than 3 dB. Frequency output was consistent and differed less than 0.7% between devices. Experiments 3 and 4: 85.2% and 83.3% of automated in-situ audiometry thresholds were within 10 dB of thresholds obtained in the sound booth and in a community setting, respectively. Acceptable test-retest intraclass correlation coefficient (ICC) was evident across all thresholds obtained in a sound booth (ICC = 0.85 to 0.93) and in a community setting (ICC = 0.83 to 0.97). CONCLUSIONS: Smartphone-facilitated in-situ audiometry allows for reliable and valid community-based testing. A simple smartphone user interface and automated in-situ audiometry allow CHWs with minimal training to facilitate the testing. With the additional capability to program hearing aids via the smartphone after the initial test, this approach would have the potential to support widespread access to personalized hearing aid fittings facilitated by CHWs in low- and middle-income countries. This approach also supports self-fitting options based on in-situ thresholds, enabling testing and fitting via over the counter hearing aids.

Effectiveness of an Over-the-Counter Self-fitting Hearing Aid Compared With an Audiologist-Fitted Hearing Aid: A Randomized Clinical Trial.

Importance: Hearing loss is a highly prevalent condition, with numerous debilitating consequences when left untreated. However, less than 20% of US adults with hearing loss use hearing aids. Over-the-counter (OTC) hearing aids became available in October 2022 to improve access and affordability. However, clinical effectiveness studies of available OTC hearing aids using the existing devices in the market are limited. Objective: To compare the clinical effectiveness of a self-fitting OTC hearing aid with remote support and a hearing aid fitted using audiologist-fitted best practices. Design, Setting, and Participants: This randomized clinical effectiveness trial was conducted between April 14 and August 29, 2022. Sixty-eight adults with self-perceived mild to moderate hearing loss were recruited and randomly assigned to either the self-fitting or the audiologist-fitted group. Following bilateral hearing aid fitting, participants first completed a 2-week, take-home field trial without any support. Access to fine-tuning for both groups was only available after the 2-week trial. Support and adjustment were provided remotely for the self-fitting group per request and by the audiologist for the audiologist-fitted group. Participants were then reassessed after an additional 4-week take-home trial. Interventions: A commercially available self-fitting OTC hearing aid was provided to participants in the self-fitting group who were expected to set up the hearing aids using the commercially supplied instructional material and accompanying smartphone application. In the audiologist-fitted group, audiologists fitted the same hearing aid according to the National Acoustics Laboratories nonlinear version 2 algorithm for prescriptive gain target using real-ear verification with hearing aid use instruction. Main Outcomes and Measures: The primary outcome measure was self-reported hearing aid benefit, measured using the Abbreviated Profile of Hearing Aid Benefit (APHAB). Secondary measures included the International Outcome Inventory for Hearing Aids (IOI-HA) and speech recognition in noise measured using an abbreviated speech-in-noise test and a digits-in-noise test. All measures were completed at baseline and at 2 intervals following hearing aid fitting (2 and 6 weeks). Results: Sixty-four participants were included in the analytic sample (33 men [51.6%]; mean [SD] age, 63.6 [14.1] years), with equal numbers of participants (n = 32) randomized into each group. The groups did not differ significantly in age (effect size r = -0.2 [95% CI, -0.3 to 0.2]) or 4-frequency pure-tone average (effect size r = 0.2 [95% CI, -0.1 to 0.4]). After the 2-week field trial, the self-fitting group had an initial advantage compared with the audiologist-fitted group on the self-reported APHAB (Cohen d = -0.5 [95% CI, -1.0 to 0]) and IOI-HA (effect size r = 0.3 [95% CI, 0.0-0.5]) but not speech recognition in noise. At the end of the 6-week trial, no meaningful differences were evident between the groups on any outcome measures. Conclusion and relevance: In this randomized clinical effectiveness trial, self-fitting OTC hearing aids with remote support yielded outcomes at 6 weeks post fitting comparable to those of hearing aids fitted using audiologist best practices. These findings suggest that self-fitting OTC hearing aids may provide an effective intervention for mild to moderate hearing loss. Trial Registration: ClinicalTrials.gov Identifier: NCT05337748.

Hearing Healthcare Professionals' Views about Over-The-Counter (OTC) Hearing Aids: Analysis of Retrospective Survey Data.

Over-the-counter hearing aids have been available to consumers in the US since 17 October 2022 following a ruling by the Food and Drug Administration. However, their reception by hearing healthcare professionals (HHP) has been mixed, and concerns have been expressed by many HHPs. The aim of this study was to examine the concerns that HHPs have towards over-the-counter (OTC) hearing aids. The study used a retrospective survey design. The survey data of HHPs (n = 730) was obtained from Hearing Tracker. A 22-item structured questionnaire was administered using a Question Scout platform. Descriptive analyses examined reported areas of concern and a Fisher's exact test examined the relationship between demographics and responses. A cluster analysis with partitioning around medoids (PAM) was used to identify a sub-group of participants based on responses. Nearly half of HHPs who participated reported that they will support patients with OTC hearing aids purchased elsewhere, whereas a quarter reported that they will sell OTC hearing aids in their clinic or website. HHPs expressed over 70% agreement in 'concern' statements in 14 of the 17 items. Issues about safety, counseling, and audiological care were the key concerns expressed by HHPs about OTC hearing aids. Some demographics (i.e., profession, primary position) were associated with responses to some statements. Two groups were identified based on the responses to concern statements. The HHPs in the first cluster 'OTC averse' (51%) agreed on all the 17 concern statements, whereas the second cluster 'OTC apprehensive' (49%) had some items rated as disagree (i.e., consumers will give up on amplification) and neither agree nor disagree (i.e., do not provide good value, warranties and return periods will be worse), and remaining items were rated as agree. OTC hearing aids were initiated to improve affordability, accessibility, and hearing aid uptake and are currently a rapidly emerging category of hearing devices. Overall, the results of the current study indicate that HHPs have serious concerns about OTC hearing aids. HHP concerns cited in this study provide useful feedback to stakeholders (e.g., HHP professional agencies, FDA, industry, and insurance payers) involved in improving OTC hearing aid implementation.

Satisfaction with hearing assessment feedback using the My Hearing Explained tool: client and audiologist perceptions.

OBJECTIVE: To determine the perceived satisfaction and understanding of hearing assessment feedback, using the Ida My Hearing Explained Tool (IMHET), compared to the standard audiogram reported by adult clients and audiologists. DESIGN: This study is a mixed-method design comparing clients and audiologists' perceptions through a single-blinded, randomised control trial and focus group discussions. After using either the audiogram or IMHET for feedback, clients and audiologists completed the adapted Patient Satisfaction Questionnaire (PSQ). STUDY SAMPLE: During client's initial audiological consultations, audiologists provided hearing assessment feedback (Total = 51) using the IMHET or audiogram. Twenty-seven clients and seven audiologists participated in focus groups, and/or open-ended questions. RESULTS: Satisfaction was not significantly different (p > 0.05) between the IMHET (76.18; SD: 2.66) or audiogram (75.63; SD: 4.73) for the overall PSQ scores reported by clients and audiologists. Two shared main themes, understanding and satisfaction, were identified for both tools from the focus groups and open-ended questions. A third main theme, recommendations, was identified only for the IMHET. CONCLUSIONS: The IMHET is a valuable resource for clients during hearing assessment feedback. Audiologists recommend that the audiogram be used as a supplement when using the IMHET to provide feedback.

Global use and outcomes of the hearWHO mHealth hearing test.

Objectives: The objective of this study was to examine the uptake, user characteristics, and performance of the free WHO smartphone hearing screening test (hearWHO) as a global hearing health promotion initiative. Method: We retrospectively examined the data of 242 626 tests conducted by adults (> 18 years) on the hearWHO app between February 2019 and May 2021. Test uptake was evaluated by country, WHO world region, test date, and demographics of age and gender. Results: The hearWHO test was completed in nearly every country globally (n = 179/195), with the greatest uptake seen in China and India. Uptake was greatest in the Western Pacific (32.9%) and European (24.8%) WHO regions. There was a high uptake of tests (44%) by young adults under the age of 30 years. 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. Most testing (49%) took place in March (2019-2021) coinciding with World Hearing Day (3rd of March) each year. Conclusions: Digital mhealth tools provide many benefits in healthcare, including health promotion, access to information, and services for hearing loss. The hearWHO test was mainly reaching younger adults, positioning it as an important measure for public health advocacy to prevent hearing loss. Since hearing loss is primarily age related, more targeted campaigns or community-based initiatives should be directed toward older adults.

Remote Monitoring of Adult Cochlear Implant Recipients Using Digits-in-Noise Self-Testing.

PURPOSE: The COVID-19 pandemic has accelerated the uptake and scope of telehealth. This study determined the accuracy and reliability of a smartphone digits-in-noise (DIN) test when conducted by adult cochlear implant (CI) recipients in a simulated home environment compared with a clinic setup. Perceptions of remote monitoring using speech-in-noise (SIN) testing were also explored. METHOD: Thirty-three adult CI recipients between 18 and 78 years of age (M = 46.7, SD = ±20.4) conducted the DIN test in a simulated home environment and a clinic setup. Test-retest reliability across the two environments and comparisons between test settings were evaluated. A survey explored the perceptions of adult CI recipients regarding remote monitoring and use of the DIN self-test. RESULTS: Mean-aided speech reception thresholds (SRTs) in the clinic and simulated home environment test conditions and clinic and simulated home environment retest conditions did not differ significantly. Mean test-retest SRTs in the clinic and simulated home environment were significantly different (p < .05). High intraclass correlation coefficient and low standard error of measurement scores reflected good and excellent reliability between test-retest measures and between clinic and simulated home environment measures. Most participants were positive about the possibility of using the DIN test at home to self-assess speech perception, although some test adjustments such as including training items and a less adverse starting signal-to-noise ratio may be required. CONCLUSION: Adult CI recipients can use the smartphone DIN test to self-assess aided SIN performance in a home environment with accuracy and reliability relatively similar to clinic testing. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.20044418.

Improving the Efficiency of the Digits-in-Noise Hearing Screening Test: A Comparison Between Four Different Test Procedures.

PURPOSE: This study compared the test characteristics, test-retest reliability, and test efficiency of three novel digits-in-noise (DIN) test procedures to a conventional antiphasic 23-trial adaptive DIN (D23). METHOD: One hundred twenty participants with an average age of 42 years (SD = 19) were included. Participants were tested and retested with four different DIN procedures. Three new DIN procedures were compared to the reference D23 version: (a) a self-selected DIN (DSS) to allow participants to indicate a subjective speech recognition threshold (SRT), (b) a combination of self-selected and adaptive eight-trial DIN (DC8) that utilized a self-selected signal-to-noise ratio (SNR) followed by an eight-trial adaptive DIN procedure, and (c) a fixed SNR DIN (DF) approach using a fixed SNR value for all presentations to produce a pass/fail test result. RESULTS: Test-retest reliability of the D23 procedure was better than that of the DSS and DC8 procedures. SRTs from DSS and DC8 were significantly higher than SRTs from D23. DSS was not accurate to discriminate between normal-hearing and hard of hearing listeners. The DF and DC8 procedures with an adapted cutoff showed good hearing screening test characteristics. All three novel DIN procedure durations were significantly shorter (< 70 s) than that of D23. DF showed a reduction of 46% in the number of presentations compared to D23 (from 23 presentations to an average of 12.5). CONCLUSIONS: The DF and DC8 procedures had significantly lower test durations than the reference D23 and show potential to be more time-efficient screening tools to determine normal hearing or potential hearing loss. Further studies are needed to optimize the DC8 procedure. The reference D23 remains the most reliable and accurate DIN hearing screening test, but studies in which the potentially efficient new DIN procedures are compared to pure-tone thresholds are needed to validate these procedures.

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.

French Version of the Antiphasic Digits-in-Noise Test for Smartphone Hearing Screening.

In France 58% of persons with hearing loss still do not wear hearing aids. Pure-tone audiometry is the traditional gold standard in assessment and screening of hearing impairment, but it requires the use of calibrated devices and soundproof booth. The antiphasic digits-in-noise (DIN) test does not require calibrated material and can run on a standard headset or earbuds connected to a smartphone or a computer. The DIN test is highly correlated with pure tone audiometry and has already shown to be effective in hearing loss screening in its English version promoted by the WHO. The aim of the present study was to develop and validate a French version of the antiphasic DIN test for implementation on a national screening test offered as a smartphone app. The audio files recorded from a French native female speaker were selected and normalized in intensity according to their recognition probability. The French DIN test application was then tested on normal hearing- and hearing-impaired subjects. Based on the strong correlation between pure tone audiometry (PTA) and DIN SRT, we calculated ROC curves and Z-score. For PTA > 20 dB HL, a SNR cutoff of 12.9 dB corresponds to a sensitivity and specificity of 0.96 and 0.93, respectively. To detect moderate and more severe hearing loss (PTA > 40 dB HL), the SNR cutoff was -10.9 dB, corresponding to a sensitivity and specificity of 0.99 and 0.83, respectively. The Z-score was calculated to define statistical criteria of normality for speech-in-noise evaluation. While a score of 0 roughly corresponds to the normality (DIN SRT = -15.4 dB SNR), a subject with DIN SRT > -12.2 (Z-score > 2) is ranked in the hearing loss population. Next, the French antiphasic DIN test was implemented in the Höra iOS and Android apps. In total, 19,545 Höra tests were completed and analyzed. Three quarters of them were classified as normal (74 %) and one quarter presented mild (9%) or more severe loss (17%). Together, results argue for the use of the French version of antiphasic DIN test in the general population to improve the screening of hearing-impaired individuals.

An analytical method to convert between speech recognition thresholds and percentage-correct scores for speech-in-noise tests.

Speech-in-noise tests use fixed signal-to-noise ratio (SNR) procedures to measure the percentage of correctly recognized speech items at a fixed SNR or use adaptive procedures to measure the SNR corresponding to 50% correct (i.e., the speech recognition threshold, SRT). A direct comparison of these measures is not possible yet. The aim of the present study was to demonstrate that these measures can be converted when the speech-in-noise test meets specific criteria. Formulae to convert between SRT and percentage-correct were derived from basic concepts that underlie standard speech recognition models. Information about the audiogram is not being used in the proposed method. The method was validated by comparing the direct conversion by these formulae with the conversion using the more elaborate Speech Intelligibility Index model and a representative set of 60 audiograms (r = 0.993 and r = 0.994, respectively). Finally, the method was experimentally validated with the Afrikaans sentence-in-noise test (r = 0.866). The proposed formulae can be used when the speech-in-noise test uses steady-state masking noise that matches the spectrum of the speech. Because pure tone thresholds are not required for these calculations, the method is widely applicable.

Speech Recognition in Noise Using Binaural Diotic and Antiphasic Digits-in-Noise in Children: Maturation and Self-Test Validity.

BACKGROUND: Digits-in-noise (DIN) tests have become popular for hearing screening over the past 15 years. Several recent studies have highlighted the potential utility of DIN as a school-aged hearing test. However, age may influence test performance in children due to maturation. In addition, a new antiphasic stimulus paradigm has been introduced, allowing binaural intelligibility level difference (BILD) to be measured by using a combination of conventional diotic and antiphasic DIN. PURPOSE: This study determined age-specific normative data for diotic and antiphasic DIN, and a derived measure, BILD, in children. A secondary aim evaluated the validity of DIN as a smartphone self-test in a subgroup of young children. RESEARCH DESIGN: A cross-sectional, quantitative design was used. Participants with confirmed normal audiometric hearing were tested with a diotic and antiphasic DIN. During the test, arrangements of three spoken digits were presented in noise via headphones at varying signal-to-noise ratio (SNR). Researchers entered each three-digit spoken sequence repeated by the participant on a smartphone keypad. STUDY SAMPLE: Overall, 621 (428 male and 193 female) normal hearing children (bilateral pure tone threshold of ≤ 20 dB hearing level at 1, 2, and 4 kHz) ranging between the ages of 6 and 13 years were recruited. A subgroup of 7-year-olds (n = 30), complying with the same selection criteria, was selected to determine the validity of self-testing. DATA COLLECTION AND ANALYSIS: DIN testing was completed via headphones coupled to a smartphone. Diotic and antiphasic DIN speech recognition thresholds (SRTs) were analyzed and compared for each age group. BILD was calculated through subtraction of antiphasic from diotic SRTs. Multiple linear regressions were run to determine the effect of age on SRT and BILD. In addition, piecewise linear regressions were fit across different age groups. Wilcoxon signed-rank tests were used to determine differences between self- and facilitated tests. RESULTS: Age was a significant predictor, of both diotic and antiphasic DIN SRTs (p < 0.05). SRTs improved by 0.15 dB and 0.35 dB SNR per year for diotic and antiphasic SRTs, respectively. However, age effects were only significant up to 10 and 12 years for antiphasic and diotic SRTs, respectively. Age significantly (p < 0.001) predicted BILD, which increased by 0.18 dB per year. A small SRT advantage for facilitated over self-testing was seen but was not significant (p > 0.05). CONCLUSIONS: Increasing age was significantly associated with improved SRT and BILD using diotic and antiphasic DINs. DIN could be used as a smartphone self-test in young children from 7 years of age with appropriate quality control measures to avoid potential false positives.

Pure-tone audiometry without bone-conduction thresholds: using the digits-in-noise test to detect conductive hearing loss.

Objective: COVID-19 has been prohibitive to traditional audiological services. No- or low-touch audiological assessment outside a sound-booth precludes test batteries including bone conduction audiometry. This study investigated whether conductive hearing loss (CHL) can be differentiated from sensorineural hearing loss (SNHL) using pure-tone air conduction audiometry and a digits-in-noise (DIN) test.Design: A retrospective sample was analysed using binomial logistic regressions, which determined the effects of pure tone thresholds or averages, speech recognition threshold (SRT), and age on the likelihood that participants had CHL or bilateral SNHL.Study sample: Data of 158 adults with bilateral SNHL (n = 122; PTA0.5-4 kHz > 25 dB HL bilaterally) or CHL (n = 36; air conduction PTA0.5-4 kHz > 25 dB HL and ≥20 dB air bone gap in the affected ears) were included.Results: The model which best discriminated between CHL and bilateral SNHL used low-frequency pure-tone average (PTA), diotic DIN SRT, and age with an area under the ROC curve of 0.98 and sensitivity and specificity of 97.2 and 93.4%, respectively.Conclusion: CHL can be accurately distinguished from SNHL using pure-tone air conduction audiometry and a diotic DIN. Restrictions on traditional audiological assessment due to COVID-19 require lower touch audiological care which reduces infection risk.

Characteristics and Help-Seeking Behavior of People Failing a Smart Device Self-Test for Hearing.

Purpose This study investigated user characteristics, help-seeking behavior, and follow-up actions of people who failed an app-based digits-in-noise hearing screening test, considering their stage of change. Method Test and user characteristics of 3,092 listeners who failed the test were retrospectively analyzed. A posttest survey determining follow-up (verb) actions was sent to listeners who failed the test (n = 1,007), of which 59 responded. Results The majority of listeners were in the precontemplation stage (75.5%). Age and stage of change were significant (p < .05) predictors of the digits-in-noise speech recognition threshold (DIN SRT). Listeners in the precontemplation stage were significantly younger than in other stages (p < .05). Posttest survey response rate was low (5.9%). Of those, most (82.4%) did not think they had a hearing loss. Only 13.6% followed up with an audiologist. Conclusion Older people presented with poorer DIN SRTs and were typically in a more advanced stage of change. The majority of those who did not follow up after failing the screening test did not believe they had a hearing loss. A combination of factors, including poor DIN SRT, older age, and a more advanced stage of change inclined participants to follow up with audiological care.

Improving Sensitivity of the Digits-In-Noise Test Using Antiphasic Stimuli.

OBJECTIVES: The digits-in-noise test (DIN) has become increasingly popular as a consumer-based method to screen for hearing loss. Current versions of all DINs either test ears monaurally or present identical stimuli binaurally (i.e., diotic noise and speech, NoSo). Unfortunately, presentation of identical stimuli to each ear inhibits detection of unilateral sensorineural hearing loss (SNHL), and neither diotic nor monaural presentation sensitively detects conductive hearing loss (CHL). After an earlier finding of enhanced sensitivity in normally hearing listeners, this study tested the hypothesis that interaural antiphasic digit presentation (NoSπ) would improve sensitivity to hearing loss caused by unilateral or asymmetric SNHL, symmetric SNHL, or CHL. DESIGN: This cross-sectional study recruited adults (18 to 84 years) with various levels of hearing based on a 4-frequency pure-tone average (PTA) at 0.5, 1, 2, and 4 kHz. The study sample was comprised of listeners with normal hearing (n = 41; PTA ≤ 25 dB HL in both ears), symmetric SNHL (n = 57; PTA > 25 dB HL), unilateral or asymmetric SNHL (n = 24; PTA > 25 dB HL in the poorer ear), and CHL (n = 23; PTA > 25 dB HL and PTA air-bone gap ≥ 20 dB HL in the poorer ear). Antiphasic and diotic speech reception thresholds (SRTs) were compared using a repeated-measures design. RESULTS: Antiphasic DIN was significantly more sensitive to all three forms of hearing loss than the diotic DIN. SRT test-retest reliability was high for all tests (intraclass correlation coefficient r > 0.89). Area under the receiver operating characteristics curve for detection of hearing loss (>25 dB HL) was higher for antiphasic DIN (0.94) than for diotic DIN (0.77) presentation. After correcting for age, PTA of listeners with normal hearing or symmetric SNHL was more strongly correlated with antiphasic (rpartial[96] = 0.69) than diotic (rpartial = 0.54) SRTs. Slope of fitted regression lines predicting SRT from PTA was significantly steeper for antiphasic than diotic DIN. For listeners with normal hearing or CHL, antiphasic SRTs were more strongly correlated with PTA (rpartial[62] = 0.92) than diotic SRTs (rpartial[62] = 0.64). Slope of the regression line with PTA was also significantly steeper for antiphasic than diotic DIN. The severity of asymmetric hearing loss (poorer ear PTA) was unrelated to SRT. No effect of self-reported English competence on either antiphasic or diotic DIN among the mixed first-language participants was observed. CONCLUSIONS: Antiphasic digit presentation markedly improved the sensitivity of the DIN test to detect SNHL, either symmetric or asymmetric, while keeping test duration to a minimum by testing binaurally. In addition, the antiphasic DIN was able to detect CHL, a shortcoming of previous monaural or binaurally diotic DIN versions. The antiphasic DIN is thus a powerful tool for population-based screening. This enhanced functionality combined with smartphone delivery could make the antiphasic DIN suitable as a primary screen that is accessible to a large global audience.

Performance and Reliability of a Smartphone Digits-in-Noise Test in the Sound Field.

Purpose This study compared the speech reception thresholds (SRTs) and test-retest reliability of the smartphone digits-in-noise (DIN) test coupled to various sound-field transducers. Method Fifty normal-hearing participants (bilateral pure- tone thresholds 0.5-8kHz ≤ 15dB HL) between the ages of 18 and 25 years (M = 20, SD = ±1.9) were recruited. The study used a repeated measure counterbalanced Latin square design to compare the SRTs of the smartphone DIN test recorded with earphones, 2 smartphone speakers, and 2 external loudspeakers in a sound booth. Test-retest reliability across sound field conditions was also determined. Results Mean SRTs across earphone and different sound field transducers ranged from -11.3 (SD = 0.8) to -11.7 (SD = 1.2). SRTs across the 4 different loudspeaker transducers and earphones were not significantly different (p > .05) between test and retest sessions. Conclusion The smartphone DIN test is reliable and can be conducted using various sound field transducers in a sound booth. To allow home-based testing without earphones, with special application to aided performance for speech-in-noise testing, the smartphone DIN test should be evaluated in home environments.

A Smartphone National Hearing Test: Performance and Characteristics of Users.

PURPOSE: The smartphone digits-in-noise hearing test, called hearZA, was made available as a self-test in South Africa in March 2016. This study determined characteristics and test performance of the listeners who took the test. METHOD: A retrospective analysis of 24,072 persons who completed a test between March 2016 and August 2017 was conducted. User characteristics, including age, English-speaking competence, and self-reported hearing difficulty, were analyzed. Regression analyses were conducted to determine predictors of the speech reception threshold. RESULTS: Overall referral rate of the hearZA test was 22.4%, and 37% of these reported a known hearing difficulty. Age distributions showed that 33.2% of listeners were ages 30 years and younger, 40.5% were between ages 31 and 50 years, and 26.4% were older than 50 years. Age, self-reported English-speaking competence, and self-reported hearing difficulty were significant predictors of the speech reception threshold. CONCLUSIONS: High test uptake, particularly among younger users, and high overall referral rate indicates that the hearZA app addresses a public health need. The test also reaches target audiences, including those with self-reported hearing difficulty and those with normal hearing who should monitor their hearing ability.