Hearing screening for school children: comparison of low-cost, computer-based and conventional audiometry

Test-Retest repeatability of automated threshold audiometry in Nicaraguan schoolchildren

OBJECTIVE

Automated threshold audiometry (ATA) could increase access to paediatric hearing assessment in low- and middle-income countries, but few studies have evaluated test-retest repeatability of ATA in children. This study aims to analyse test-retest repeatability of ATA and to identify factors that affect the reliability of this method.

DESIGN

ATA was performed twice in a cohort of Nicaraguan schoolchildren. During testing, the proportion of responses occurring in the absence of a stimulus was measured by calculating a stimulus response false positive rate (SRFP). Absolute test-retest repeatability was determined between the two trials, as well as the impact of age, gender, ambient noise, head circumference, and SRFP on these results.

STUDY SAMPLE

807 children were randomly selected from 35 schools in northern Nicaragua.

RESULTS

Across all frequencies, the absolute value of the difference between measurements was 5.5 ± 7.8 dB. 89.6% of test-retest differences were within 10 dB. Intra-class correlation coefficients between the two measurements showed that lower SRFP was associated with improved repeatability. No effect of age, gender, or ambient noise was found.

CONCLUSIONS

ATA produced moderate test-retest repeatability in Nicaraguan schoolchildren. Participant testing behaviours, such as delayed or otherwise inappropriate response patterns, significantly impacts the repeatability of these measurements.

School Hearing Screening With a Portable, Tablet-Based, Noise-Attenuating Audiometric Headset in Rural Nicaragua

OBJECTIVE

To investigate the utility and effectiveness of a noise-attenuating, tablet-based mobile health system combined with asynchronous telehealth evaluations for screening rural Nicaraguan schoolchildren for hearing loss.

STUDY DESIGN

Prospective population-based survey.

SETTING

Rural Nicaraguan communities.

PATIENTS

There were 3,398 school children 7 to 9 years of age.

INTERVENTIONS

Diagnostic automated and manual audiometry, detailed asynchronous telehealth evaluations.

MAIN OUTCOME MEASURES

Referral rates, ambient noise levels, and audiometric results as well as hearing loss prevalence, types, and risk factors.

RESULTS

Despite high ambient noise levels during screening (46.7 dBA), no effect of noise on referral rates on automated audiometry or confirmatory manual audiometry in those who failed automated testing was seen. The overall audiometric referral rate was 2.6%. Idiopathic sensorineural hearing loss (SNHL) and cerumen impaction were the most common types of hearing loss in this population with an estimated prevalence of hearing loss (all types) of 18.3 per 1,000 children. SNHL was associated with both drug exposure during pregnancy (p = 0.04) and pesticide exposure in the home (p = 0.03).

CONCLUSION

Hearing screening using a tablet-based, noise-attenuating wireless headset audiometer is feasible and effective in rural low-resource environments with moderately elevated ambient noise levels. The referral rate with noise-attenuating headsets was much lower than that previous reports on this population. In addition, manual audiometry resulted in much lower referral rates than automated audiometry. The confirmed hearing loss rate in this study is comparable to reports from other low-income countries that use some form of noise attenuation during screening. Pesticide exposure and drug exposure during pregnancy are potential causes of SNHL in this population.

Community health workers and mHealth systems for hearing screening in rural Nicaraguan schoolchildren

Background

We aimed to investigate the effectiveness of using minimally trained community health workers (CHW) to screen schoolchildren in rural Nicaragua for hearing loss using a tablet-based audiometric system integrated with asynchronous telehealth evaluations and mobile health (mHealth) appointment reminders.

Methods

A population-based survey was conducted using community health workers (CHWs) to perform tablet-based audiometry, asynchronous telehealth evaluations, and mHealth reminders to screen 3398 school children (7-9 years of age) in 92 rural Nicaraguan communities. The accuracy of screening, test duration, testing efficiency, telehealth data validity, and compliance with recommended clinic visits were analyzed.

Results

Minimally trained CHWs successfully screened children within remote rural schools with automated audiometry (test duration = 5.8 minutes) followed by manual audiometry if needed (test duration = 4.3 minutes) with an estimated manual audiometry validity of 98.5% based on a review of convergence patterns. For children who were referred based on audiometry, the otoscopy and tympanometry obtained during telehealth evaluations were high quality (as reviewed by 3 experts) in 44.6% and 80.1% of ears, respectively. A combination of automated short message service (SMS) text messages and voice reminders resulted in a follow-up compliance of 75.2%. No families responded to SMS messages alone.

Conclusions

Tablet-based hearing screening administered by minimally trained CHWs is feasible and effective in low- and middle-income countries. Manual audiometry was as efficient as automated audiometry in this setting. The physical exam tasks of otoscopy and tympanometry require additional training. Mobile phone messages improve compliance for confirmatory audiometry, but the utility of SMS messaging alone is unclear in this population.

Diagnostic Accuracy of Smartphone-Based Audiometry for Hearing Loss Detection: Meta-analysis

Background

Hearing loss is one of the most common disabilities worldwide and affects both individual and public health. Pure tone audiometry (PTA) is the gold standard for hearing assessment, but it is often not available in many settings, given its high cost and demand for human resources. Smartphone-based audiometry may be equally effective and can improve access to adequate hearing evaluations.

Objective

The aim of this systematic review is to synthesize the current evidence of the role of smartphone-based audiometry in hearing assessments and further explore the factors that influence its diagnostic accuracy.

Methods

Five databases—PubMed, Embase, Cochrane Library, Web of Science, and Scopus—were queried to identify original studies that examined the diagnostic accuracy of hearing loss measurement using smartphone-based devices with conventional PTA as a reference test. A bivariate random-effects meta-analysis was performed to estimate the pooled sensitivity and specificity. The factors associated with diagnostic accuracy were identified using a bivariate meta-regression model. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

Results

In all, 25 studies with a total of 4470 patients were included in the meta-analysis. The overall sensitivity, specificity, and area under the receiver operating characteristic curve for smartphone-based audiometry were 89% (95% CI 83%-93%), 93% (95% CI 87%-97%), and 0.96 (95% CI 0.93-0.97), respectively; the corresponding values for the smartphone-based speech recognition test were 91% (95% CI 86%-94%), 88% (95% CI 75%-94%), and 0.93 (95% CI 0.90-0.95), respectively. Meta-regression analysis revealed that patient age, equipment used, and the presence of soundproof booths were significantly related to diagnostic accuracy.

Conclusions

We have presented comprehensive evidence regarding the effectiveness of smartphone-based tests in diagnosing hearing loss. Smartphone-based audiometry may serve as an accurate and accessible approach to hearing evaluations, especially in settings where conventional PTA is unavailable.

Calibration and initial validation of a low-cost computer-based screening audiometer coupled to consumer insert phone-earmuff combination for boothless audiometry

OBJECTIVE

To undertake calibration and preliminary validation of a custom-designed computer-based screening audiometer connected to consumer insert phone-earmuff combination for adult pure tone audiometry.

DESIGN

Part 1 involved electroacoustic measurement and biological calibration of a laptop-earphone pair used for the computer-based audiometry (CBA). Part 2 compared CBA thresholds obtained without a sound booth with those measured using the gold-standard clinical audiometry.

STUDY SAMPLE

17 young normal-hearing volunteers (Part 1) and 43 normal and hearing loss subjects (Part 2) recruited from an audiology clinic via convenience sampling.

RESULTS

The transducer-device combination produced outputs suitable for measuring thresholds down to 0 dB HL. Threshold pairs obtained from the CBA and clinical audiometry were highly correlated (Spearman's correlation coefficient, ρ = 0.92, p < 0.0001) and had a good degree of agreement (mean difference of -1.06 ± 7.63 dB). Also, the CBA showed about 90% sensitivity and 80% specificity for detecting hearing loss based on low (0.5, 1, 2 kHz) and high frequency (4, 8 kHz) pure tone averages of >25 dB HL.

CONCLUSIONS

The use of a computer-based audiometer application with consumer insert phone-earmuff combination can offer a cost-effective solution for boothless screening audiometry.

Contextually appropriate school entry hearing screening protocol for low- and middle-income countries: A scoping review

BACKGROUND

In low- and middle-income countries (LMICs), where universal newborn hearing screening programmes are often not available, school entry hearing screening programmes serve as a safeguard for early detection and intervention for hearing loss in school learners.

OBJECTIVE

To determine a contextually appropriate school entry hearing screening protocol for LMICs.

METHODS

A scoping review was utilised to comprehensively search for relevant publications in the following electronic databases: Africa-Wide Information, CINAHL, Health Source: Nursing/Academic Edition, Cochrane Library, Pubmed, Scopus, and Web of Science. Studies included those that investigated school-based hearing screening protocols or programmes for LMICs among learners aged five to twelve years. The review was conducted and reported according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews checklist.

RESULTS

The search yielded 1863 studies, and after removing duplicates and ineligible studies, 19 studies were selected for data extraction. Pure tone audiometry screening was the most frequently used age-appropriate hearing screening test in the reviewed studies (n = 17). Conducting pure tone audiometry screening using 1, 2, and 4 kHz frequency combination resulted in referral rates ranging from 3.2% to 21%. In studies that included 0.5 kHz to the screening frequencies, referral rates ranged from 5.8% to 56%. Screening at 25 dB HL intensity level yielded referral rates ranging from 3.2% to 10.3%. Immediate rescreening reduced overall referral rates for learners referred for audiological diagnostic testing by up to 57%. Ambient noise levels were controlled by conducting screening in quiet rooms (n = 14) and utilising screening equipment that allows for monitoring and reducing environmental noise (n = 3).

CONCLUSION

An ideal school entry hearing screening protocol in LMIC contexts could potentially utilise pure tone audiometry screening at 1, 2, and 4 kHz, using 25 dB HL screening intensity level with an immediate rescreen for learners with a refer result. School entry hearing screening should be conducted in a quiet room, preferably using hearing screening equipment capable of monitoring ambient noise levels to reduce false positive referrals.

Referral Criteria for Preschool Hearing Screening in Resource-Constrained Settings: A Comparison of Protocols

Purpose This study aimed to describe and compare the performance of two screening protocols used for preschool hearing screening in resource-constrained settings. Method Secondary data analysis was done to determine the performance of two protocols implemented during a preschool hearing screening program using mobile health technology in South Africa. Pure-tone audiometry screening at 25 dB HL for 1000, 2000, and 4000 Hz in each ear was used by both protocols. The fail criterion for the first protocol (2,147 children screened) constituted a no-response on one or more frequencies in either ear. The second protocol required two or more no-responses (5,782 children). Multivariate logistic regression models were used to investigate associations between outcomes and protocol, age, gender, and duration. Results Fail rates for the one-frequency fail protocol was 8.7% (n = 186) and 4.3% (n = 250) for the two-frequency fail protocol. Children screened with the two-frequency fail protocol were 52.9% less likely to fail (p < .001; OR = 0.471; 95% confidence interval [0.385, 0.575]). Gender (p = .251) and age (p = .570) had no significant effect on screening outcome. A percentage of cases screened (44.7%) exceeded permissible noise levels in at least one ear at 1000 Hz across both protocols. True- and false-positive cases did not differ significantly between protocols. Protocol type (p = .204), gender (p = .314), and age (p = .982) did not affect the odds of being a true-positive result. Average screening time was 72.8 s (78.66 SD) and 64.9 s (55.78 SD) for the one-frequency and two-frequency fail protocols, respectively. Conclusions A two-frequency fail criterion and immediate rescreen of failed frequencies significantly reduced referral rate for follow-up services that are often overburdened in resourced-constrained settings. Future protocol adaptations can also consider increasing the screening levels at 1000 Hz to minimize the influence of environmental noise.

Assessment of hearing screening programmes across 47 countries or regions III: provision of childhood hearing screening after the newborn period

OBJECTIVE

To inventory provision and features of childhood hearing screening after the newborn period (CHS), primarily in Europe.

DESIGN

From each participating country or region, experts provided information through an extensive questionnaire: implementation year, age at screening, test method, pass criteria, screening location, screener profession, and quality indicators: coverage, referral, follow-up and detection rates, supplemented by literature sources.

STUDY SAMPLE

Forty-two European countries or regions, plus Russia, Malawi, Rwanda, India, and China.

RESULTS

CHS was performed universally with pure-tone audiometry screening (PTS) in 17 countries or regions, whereas non-universal CHS was performed in eight with PTS or whisper tests. All participating countries with universal PTS had newborn hearing screening. Coverage rate was provided from three countries, detection rate from one, and referral and follow-up rate from two. In four countries, universal PTS was performed at two ages. Earliest universal PTS was performed in a (pre)school setting by nurses (n = 9, median age: 5 years, range: 3-7), in a healthcare setting by doctors and nurses (n = 7, median age: 4.5 years, range: 4-7), or in both (n = 1).

CONCLUSIONS

Within universal CHS, PTS was mostly performed at 4-6 years by nurses. Insufficient collection of data and monitoring with quality indicators impedes evaluation of screening.

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; PTA_0.5-4 kHz > 25 dB HL bilaterally) or CHL (n = 36; air conduction PTA_0.5-4 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.

Speech production abilities of 4- to 5-year-old children with and without a history of late talking: The tricky tyrannosaurus

Purpose: Research on the speech production abilities of children with a history of late talking (HLT) is limited. We compared 4- to 5-year-old children with and without a HLT on a routine speech assessment and a single-word polysyllable assessment.Method: The two speech assessments were administered to 13 children with a HLT (4;4-5;9 years) and 11 children with a history of typical development (HTD) (4;1-5;10 years). Data were analysed using descriptive and inferential statistics.Result: The HLT group had significantly poorer speech accuracy than the HTD group on both the routine speech and polysyllable assessments. The HLT group also showed a significantly higher percentage occurrence of consonant omissions on both speech assessments compared to the HTD group. Descriptive analysis of participants' polysyllable productions indicated that the HLT group showed a higher percentage occurrence of a range of error types compared to the HTD group.Conclusion: By 4-5 years of age, children who were late to talk had speech production abilities that were significantly poorer than their peers who were not late to talk, suggesting continued underlying differences.

The Professional's experience with causes of delay in the diagnosis and management of children with a congenital hearing loss in Libya

The aim of this study was to collect and interpret narrative and observational data from Audiologists and ENT doctors' experiences of delays in the identification and management of congenital hearing loss (CHL) in Libya. This qualitative study sought to explore and understand the reasons behind the delay. Participants were three Audiological Physicians and five Otolarngologists (ENT) working in public hospitals in four large cities in Libya. They were interviewed to explore the causes of such delays and themes were generated from their experiences. All participants revealed that the main causes might be associated with limited facilities and availability of audiology services, lack of awareness and knowledge of the magnitude of the issue and the importance of early detection and intervention for CHL in Libya. In contrast to other developing countries, the financial situation and poverty were not considered to be the main cause in Libya. Furthermore, socioeconomic status of the children's families appears relevant.

The UNICEF/Washington Group Child Functioning Module-Accuracy, Inter-Rater Reliability and Cut-Off Level for Disability Disaggregation of Fiji's Education Management Information System

This paper explores the validity (sensitivity and specificity) of different cut-off levels of the UNICEF/Washington Group Child Functioning Module (CFM) and the inter-rater reliability between teachers and parents as proxy respondents, for disaggregating Fiji's education management information system (EMIS) by disability. The method used was a cross-sectional diagnostic accuracy study comparing CFM items to standard clinical assessments for 472 primary school aged students in Fiji. Whilst previous domain-specific results showed "good" to "excellent" accuracy of the CFM domains seeing, hearing, walking and speaking, newer analysis shows only "fair" to "poor" accuracy of the cognitive domains (learning, remembering and focusing attention) and "fair" of the overall CFM (area under the Receiver Operating Characteristic curve: 0.763 parent responses, 0.786 teacher responses). Severe impairments are reported relatively evenly across CFM response categories "some difficulty", "a lot of difficulty" and "cannot do at all". Most moderate impairments are reported as "some difficulty". The CFM provides a core component of data required for disaggregating Fiji's EMIS by disability. However, choice of cut-off level and mixture of impairment severity reported across response categories are challenges. The CFM alone is not accurate enough to determine funding eligibility. For identifying children with disabilities, the CFM should be part of a broader data collection including learning and support needs data and undertaking eligibility verification visits.

Tablet-based tele-audiometry: Automated hearing screening for schoolchildren

Introduction

To assess the performance of a tablet-based tele-audiometry method for automated hearing screening of schoolchildren through a comparison of the results of various hearing screening approaches.

Methods

A total of 244 children were evaluated. Tablet-based screening results were compared with gold-standard pure-tone audiometry. Acoustic immittance measurements were also conducted. To pass the tablet-based screening, the children were required to respond to at least two out of three sounds for all the frequencies in each ear. Several hearing screening methods were analysed: exclusively tablet-based (with and without 500 Hz checked) and combined tests (series and parallel). The sensitivity, specificity, positive and negative predictive values and accuracy were calculated.

Results

A total of 9.43% of children presented with mild to moderate conductive hearing loss (unilateral or bilateral). Diagnostic values varied among the different hearing screening approaches that were evaluated: sensitivities ranged from 60 to 95%, specificities ranged from 44 to 91%, positive predictive values ranged from 15 to 44%, negative predictive values ranged from 95 to 99%, accuracy values ranged from 49 to 88%, and area under curve values ranged from 0.690 to 0.883. Regarding diagnostic values, the highest results were found for the tablet-based screening method and for the series approach.

Discussion

Compared with the results obtained by conventional audiometry and considering the diagnostic values of the different hearing screening approaches, the highest diagnostic values were generally obtained using the automated hearing screening method (including 500 Hz). Thus, this application, which was developed for the tablet computer, was shown to be a valuable hearing screening tool for use with schoolchildren. Therefore, we suggest that this hearing screening protocol has the potential to improve asynchronous tele-audiology service delivery.

Mobile Hearing Testing Applications and the Diagnosis of Sudden Sensorineural Hearing Loss: A Cautionary Tale

OBJECTIVE

Mobile hearing applications (apps) are available for hearing testing, personal sound amplification, as well as hearing aid modulation. Hearing testing apps are gaining popularity, especially in resource-limited settings. The reliability of mobile hearing testing apps, however, is not well characterized.

PATIENTS/INTERVENTIONS

A case study of a single patient with a complaint of sudden hearing loss presenting to a tertiary-care hospital.

MAIN OUTCOME MEASURE

Comparison of a mobile hearing testing app results with standard audiogram.

RESULTS

A commercially available mobile hearing testing app was used after hours to determine if a patient's hearing complaints were consistent with sudden sensorineural hearing loss. The hearing app produced a rudimentary audiogram that was consistent with unilateral SSNHL. Given contraindications to oral treatment, preparations for possible intratympanic dexamethasone after a full audiometric evaluation were completed. Confirmatory audiogram the following day demonstrated normal hearing without evidence of hearing loss. Steroid treatment was aborted and appropriate counseling provided.

CONCLUSION

While mobile hearing testing apps offer improved access to hearing screening in resource-limited settings, caution must be exercised when interpreting data and making clinical decisions based upon results. The role of professional audiologists remains critical. Further testing and validation of specific apps is required.

Development of Improved Software Intelligent System for Audiological Solutions

Of late, there has been an increase in hearing impairment cases and to provide the most advantageous solutions to them is an uphill task for audiologists. Significant difficulty faced by the audiologists is in effective programming of hearing aids to provide enhanced satisfaction to the users. The main aim of our study was to develop a software intelligent system (SIS): (i) to perform the required audiological investigations for finding the degree and type of hearing loss, and (ii) to suggest appropriate values of hearing aid parameters for enhancing the speech intelligibility and the satisfaction level among the hearing aid users. In this paper, we present a Neuro-Fuzzy based SIS to automatically predict and suggest the hearing-aid parameters such as gain values, compression ratio and threshold knee point, which are needed to be fixed for different octave frequencies of sound inputs during the hearing-aid trial. The test signals for audiological investigations are generated through the standard hardware present in a personal computer system and with the aid of a software algorithm. The proposed system was validated with 243 subjects' data collected at the Government General Hospital, Chennai, India. The calculated sensitivity, specificity and accuracy of the proposed audiometer incorporated in the SIS were 98.6%, 96.4 and 98.2%, respectively, by comparing its interpretations with those of the 'gold standard' audiometers. Furthermore, 91% (221 of 243) of the hearing impaired subjects attained satisfaction in the first hearing aid trials itself with the gain values as recommended by the improved SIS. The proposed system reduced around 75% of the 'trial and error' time spent by audiologists for enhancing satisfactory usage of the hearing aid. Hence, the proposed SIS could be used to find the degree and type of hearing loss and to recommend hearing aid parameters to provide optimal solutions to the hearing aid users.

A programme of studies including assessment of diagnostic accuracy of school hearing screening tests and a cost-effectiveness model of school entry hearing screening programmes

BACKGROUND

Identification of permanent hearing impairment at the earliest possible age is crucial to maximise the development of speech and language. Universal newborn hearing screening identifies the majority of the 1 in 1000 children born with a hearing impairment, but later onset can occur at any time and there is no optimum time for further screening. A universal but non-standardised school entry screening (SES) programme is in place in many parts of the UK but its value is questioned.

OBJECTIVES

To evaluate the diagnostic accuracy of hearing screening tests and the cost-effectiveness of the SES programme in the UK.

DESIGN

Systematic review, case-control diagnostic accuracy study, comparison of routinely collected data for services with and without a SES programme, parental questionnaires, observation of practical implementation and cost-effectiveness modelling.

SETTING

Second- and third-tier audiology services; community.

PARTICIPANTS

Children aged 4-6 years and their parents.

MAIN OUTCOME MEASURES

Diagnostic accuracy of two hearing screening devices, referral rate and source, yield, age at referral and cost per quality-adjusted life-year.

RESULTS

The review of diagnostic accuracy studies concluded that research to date demonstrates marked variability in the design, methodological quality and results. The pure-tone screen (PTS) (Amplivox, Eynsham, UK) and HearCheck (HC) screener (Siemens, Frimley, UK) devices had high sensitivity (PTS ≥ 89%, HC ≥ 83%) and specificity (PTS ≥ 78%, HC ≥ 83%) for identifying hearing impairment. The rate of referral for hearing problems was 36% lower with SES (Nottingham) relative to no SES (Cambridge) [rate ratio 0.64, 95% confidence interval (CI) 0.59 to 0.69; p < 0.001]. The yield of confirmed cases did not differ between areas with and without SES (rate ratio 0.82, 95% CI 0.63 to 1.06; p = 0.12). The mean age of referral did not differ between areas with and without SES for all referrals but children with confirmed hearing impairment were older at referral in the site with SES (mean age difference 0.47 years, 95% CI 0.24 to 0.70 years; p < 0.001). Parental responses revealed that the consequences to the family of the referral process are minor. A SES programme is unlikely to be cost-effective and, using base-case assumptions, is dominated by a no screening strategy. A SES programme could be cost-effective if there are fewer referrals associated with SES programmes or if referrals occur more quickly with SES programmes.

CONCLUSIONS

A SES programme using the PTS or HC screener is unlikely to be effective in increasing the identified number of cases with hearing impairment and lowering the average age at identification and is therefore unlikely to represent good value for money. This finding is, however, critically dependent on the results of the observational study comparing Nottingham and Cambridge, which has limitations. The following are suggested: systematic reviews of the accuracy of devices used to measure hearing at school entry; characterisation and measurement of the cost-effectiveness of different approaches to the ad-hoc referral system; examination of programme specificity as opposed to test specificity; further observational comparative studies of different programmes; and opportunistic trials of withdrawal of SES programmes.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN61668996.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 36. See the NIHR Journals Library website for further project information.

Hearing Tests Based on Biologically Calibrated Mobile Devices: Comparison With Pure-Tone Audiometry

BACKGROUND

Hearing screening tests based on pure-tone audiometry may be conducted on mobile devices, provided that the devices are specially calibrated for the purpose. Calibration consists of determining the reference sound level and can be performed in relation to the hearing threshold of normal-hearing persons. In the case of devices provided by the manufacturer, together with bundled headphones, the reference sound level can be calculated once for all devices of the same model.

OBJECTIVE

This study aimed to compare the hearing threshold measured by a mobile device that was calibrated using a model-specific, biologically determined reference sound level with the hearing threshold obtained in pure-tone audiometry.

METHODS

Trial participants were recruited offline using face-to-face prompting from among Otolaryngology Clinic patients, who own Android-based mobile devices with bundled headphones. The hearing threshold was obtained on a mobile device by means of an open access app, Hearing Test, with incorporated model-specific reference sound levels. These reference sound levels were previously determined in uncontrolled conditions in relation to the hearing threshold of normal-hearing persons. An audiologist-assisted self-measurement was conducted by the participants in a sound booth, and it involved determining the lowest audible sound generated by the device within the frequency range of 250 Hz to 8 kHz. The results were compared with pure-tone audiometry.

RESULTS

A total of 70 subjects, 34 men and 36 women, aged 18-71 years (mean 36, standard deviation [SD] 11) participated in the trial. The hearing threshold obtained on mobile devices was significantly different from the one determined by pure-tone audiometry with a mean difference of 2.6 dB (95% CI 2.0-3.1) and SD of 8.3 dB (95% CI 7.9-8.7). The number of differences not greater than 10 dB reached 89% (95% CI 88-91), whereas the mean absolute difference was obtained at 6.5 dB (95% CI 6.2-6.9). Sensitivity and specificity for a mobile-based screening method were calculated at 98% (95% CI 93-100.0) and 79% (95% CI 71-87), respectively.

CONCLUSIONS

The method of hearing self-test carried out on mobile devices with bundled headphones demonstrates high compatibility with pure-tone audiometry, which confirms its potential application in hearing monitoring, screening tests, or epidemiological examinations on a large scale.

Validating the UNICEF/Washington Group Child Functioning Module for Fijian schools to identify seeing, hearing and walking difficulties

PURPOSE

This study investigated the seeing, hearing and walking questions of the UNICEF/Washington Group Child Functioning Module and the inter-rater reliability between teachers and parents as proxy respondents.

METHODS

Cross-sectional diagnostic accuracy study, two-gate design with representative sampling, comparing Module responses to reference standard assessments for 472 primary aged students in Fiji. Receiver operating characteristic curves were constructed to determine the area under the curve and optimal cut-off points.

RESULTS

Areas under the curves ranged from 0.823 to 0.889 indicating "good" diagnostic accuracy. Inter-rater reliability between parent and teacher responses was "good" to "excellent". The optimal cut-off determined by the Youden Index was "some difficulty" however a wide spread of impairment levels were found in this category with most children either having none or substantial impairments.

CONCLUSIONS

The diagnostic accuracy of the Module seeing, hearing and walking questions appears acceptable with either parents or teachers as proxy respondents. For education systems, use of the cut-off "some difficulty" with accompanying clinical assessment may be important to capture children who require services and learning supports and avoid potentially misleading categorization. Given the high proportion of the sample from special schools research is required to further test the Module in mainstream schools. Implications for rehabilitation Identification of children who are at risk of disability in Fiji is important to enable planning, monitoring and evaluating access to quality inclusive education. The UNICEF/Washington Group Child Functioning Module appears to be a practical and effective tool that can be used by teachers to identify children at risk of disability. Children identified on the UNICEF/Washington Group Child Functioning Module as having "some difficulty" or higher levels of difficulty in relation to vision, hearing or walking should be referred for further assessment and services. Rehabilitation services in Fiji need to prepare for greater numbers of referrals as the Ministry of Education increasingly rolls out the inclusive education policy, which includes identification by schools of children at risk of disability.

A directly comparative two-gate case-control diagnostic accuracy study of the pure tone screen and HearCheck screener tests for identifying hearing impairment in school children

OBJECTIVES

This study directly compared the accuracy of two audiometry-based tests for screening school children for hearing impairment: the currently used test, pure tone screen and a device newly applied to children, HearCheck Screener.

DESIGN

Two-gate case-control diagnostic test accuracy study.

SETTING AND PARTICIPANTS

Hearing impaired children ('intended cases') aged 4-6 years were recruited between February 2013 and August 2014 from collaborating audiology services. Children with no previously identified impairment ('intended controls') were recruited from Foundation and Year 1 of schools between February 2013 and June 2014 in central England. The reference standard was pure tone audiometry. Tests were administered at Nottingham Hearing Biomedical Research Unit or, for some intended cases only, in the participant's home.

MAIN OUTCOME MEASURES

Sensitivity and specificity of the pure tone screen and HearCheck tests based on pure tone audiometry result as reference standard.

RESULTS

315 children (630 ears) were recruited; 75 from audiology services and 240 from schools. Full test and reference standard data were obtained for 600 ears; 155 ears were classified as truly impaired and 445 as truly hearing based on the pure tone audiometry assessment. Sensitivity was estimated to be 94.2% (95% CI 89.0% to 97.0%) for pure tone screen and 89.0% (95% CI 82.9% to 93.1%) for HearCheck (difference=5.2% favouring pure tone screen; 95% CI 0.2% to 10.1%; p=0.02). Estimates for specificity were 82.2% (95% CI 77.7% to 86.0%) for pure tone screen and 86.5% (95% CI 82.5% to 89.8%) for HearCheck (difference=4.3% favouring HearCheck; 95% CI0.4% to 8.2%; p=0.02).

CONCLUSION

Pure tone screen was better than HearCheck with respect to sensitivity but inferior with respect to specificity. As avoiding missed cases is arguably of greater importance for school entry screening, pure tone screen is probably preferable in this context.

STUDY REGISTRATION NUMBER

Current controlled trials: ISRCTN61668996.

Otoacoustic Emissions in Rural Nicaragua: Cost Analysis and Implications for Newborn Hearing Screening

Objective (1) Determine the incidence and risk factors for congenital hearing loss. (2) Perform cost analysis of screening programs. Study Design Proportionally distributed cross-sectional survey. Setting Jinotega, Nicaragua. Subjects and Methods Otoacoustic emissions (OAEs) were used to screen 640 infants <6 months of age from neonatal intensive care unit, institutional, and home birth settings. Data on 15 risk factors were analyzed. Cost of 4 implementation strategies was studied: universal screening, screening at the regional health center (RHC), targeted screening, and screening at the RHC plus targeted screening. Cost-effectiveness analysis over 10 years was based on disability-adjusted life year estimates, with the World Health Organization standard of cost-effectiveness ratio (CER) / gross domestic product (GDP) <3, with GDP set at $4884.15. Results Thirty-eight infants failed the initial OAE (5.94%). In terms of births, 325 (50.8%) were in the RHC, 69 (10.8%) in the neonatal intensive care unit, and 29 (4.5%) at home. Family history and birth defect were significant in univariate analysis; birth defect was significant in multivariate analysis. Cost-effectiveness analysis demonstrated that OAE screening is cost-effective without treatment (CER/GDP = 0.06-2.00) and with treatment (CER/GDP = 0.58-2.52). Conclusions Our rate of OAE failures was comparable to those of developed countries and lower than hearing loss rates noted among Nicaraguan schoolchildren, suggesting acquired or progressive etiology in the latter. Birth defects and familial hearing loss correlated with OAE failure. OAE screening of infants is feasible and cost-effective in rural Nicaragua, although highly influenced by estimated hearing loss severity in identified infants and the high travel costs incurred in a targeted screening strategy.

School entry level tele-hearing screening in a town in South India - Lessons learnt

INTRODUCTION

School screening is warranted in developing countries that do not have newborn hearing screening as schools provide access to a large number of young children between 3 and 5 years of age. Due to scarcity of technical manpower and equipment, hearing screening programs are not often conducted in developing countries. In these circumstances, telehealth services appear to be a reasonable solution. Consequently, the purpose of this study was to assess the feasibility of school hearing screening using telehealth technology operated by a practitioner located 400 kms away at a distant hospital.

METHOD

Thirty one children received hearing screening procedures in their school. Each child was screened for both in-person and telehealth conditions to assess screening results. Remote computing software was employed for the telehealth condition in order for the practitioner to remotely operate an audiometer, DPOAE system and a video otoscope interfaced to a personal computer at the school site.Teamviewer version 10 was used to provide encrypted videoconferencing and synchronous hearing screening services between the hospital and school sites. All screening was conducted using a mobile phone hotspot or dongle device based internet connection to insure reliable connectivity.

RESULTS

The outcome revealed no significant difference between PTA and DPOAE performed in-person and tele-hearing screening methods. Concurrence of greater than 87% was achieved between in-person and tele-video-otoscopy. Strengths and challenges were documented for tele-hearing screening in three different dimensions: technical issues, child related and school related. Understanding these challenges may provide more effective tele-audiology services.

DISCUSSION

The results of the study indicate synchronous hearing screening services can be provided in a school setting using mobile hotspot or dongle connectivity in locations where Internet bandwidth is otherwise restricted.

Software intelligent system for effective solutions for hearing impaired subjects

PURPOSE

The anatomy and physiology of the ear is complex in nature, which makes it a challenge for audiologists to prescribe solutions for varied hearing-impaired subjects. There is a need to increase the satisfaction level of hearing-aid users by adopting better strategies that involve modern technological advancements.

AIM

To design and develop a decision support Software Intelligent System (SIS) that performs audiological investigations to assess the degree of hearing loss and to suggest appropriate hearing-aid gain values.

METHODS

SIS is developed based on the study conducted in the Government General Hospital, Chennai, India, between 2013 and 2015. In the study period, audiological investigations were performed on 368 subjects, using the clinical audiometer (Inventis-Piano, Italy) and the SIS. Gain suggestions were recommended for hearing-aid users (Siemens Intuis life & Intuis-SP) using standard prescriptive procedures, alterations made by the audiologists, and by the SIS. It was developed with artificial neural network-based gain predictions.

RESULTS

Of the tested subjects, 256 were identified as hearing-impaired. The calculated sensitivity, specificity and accuracy of the computerised audiometer incorporated in the SIS are 93%, 85% and 90% respectively. Furthermore, 86% of the hearing-impaired subjects were satisfied during their first hearing-aid trial with the gain recommendations from SIS.

CONCLUSION

The findings suggest that the proposed SIS could be used to perform audiological screening tests and to recommend appropriate hearing-aid gain values to the hearing-impaired subjects. This could eventually be helpful for audiologists in the areas where routine mass audiological screening and fast hearing-aid solution is required.

Tablet Audiometry in Canada’s North

Background

Access to hearing health care is limited in many parts of the world, creating a lack of prompt diagnosis, which further complicates treatment. The use of portable audiometry for hearing loss testing can improve access to diagnostics in marginalized populations. Our study objectives were twofold: (1) to determine the prevalence of hearing loss in children aged 4 to 11 years in Iqaluit, Nunavut, and (2) to test and demonstrate the use of our tablet audiometer as a portable hearing-testing device in a remote location.

Study Design

Prospective cross-sectional observational.

Setting

Remote elementary schools in 3 Canadian Northern communities.

Subjects and Methods

Tablet audiometers were used to test hearing in 218 children. Air conduction pure tones thresholds were obtained at 500, 1000, 2000, and 4000 Hz. Children with hearing loss ≥30 dB in either ear were referred for audiology services.

Results

Tablet audiometry screening testing revealed abnormal results in 14.8% of the study participants. No significant difference in the rate of hearing loss was seen by sex; however, the rate of hearing loss decreased significantly with increasing age. The median duration of the hearing test was 5 minutes 30 seconds.

Conclusions

Of the study population, 14.8% tested positive for hearing loss based on our interactive tablet audiometer. In this setting, the tablet audiometer was both time efficient and largely language independent. This type of testing is valuable for providing much-needed hearing health care for high-risk populations in rural and remote areas where audiology services are often unavailable.

Hearing Tests on Mobile Devices: Evaluation of the Reference Sound Level by Means of Biological Calibration

Background

Hearing tests carried out in home setting by means of mobile devices require previous calibration of the reference sound level. Mobile devices with bundled headphones create a possibility of applying the predefined level for a particular model as an alternative to calibrating each device separately.

Objective

The objective of this study was to determine the reference sound level for sets composed of a mobile device and bundled headphones.

Methods

Reference sound levels for Android-based mobile devices were determined using an open access mobile phone app by means of biological calibration, that is, in relation to the normal-hearing threshold. The examinations were conducted in 2 groups: an uncontrolled and a controlled one. In the uncontrolled group, the fully automated self-measurements were carried out in home conditions by 18- to 35-year-old subjects, without prior hearing problems, recruited online. Calibration was conducted as a preliminary step in preparation for further examination. In the controlled group, audiologist-assisted examinations were performed in a sound booth, on normal-hearing subjects verified through pure-tone audiometry, recruited offline from among the workers and patients of the clinic. In both the groups, the reference sound levels were determined on a subject’s mobile device using the Bekesy audiometry. The reference sound levels were compared between the groups. Intramodel and intermodel analyses were carried out as well.

Results

In the uncontrolled group, 8988 calibrations were conducted on 8620 different devices representing 2040 models. In the controlled group, 158 calibrations (test and retest) were conducted on 79 devices representing 50 models. Result analysis was performed for 10 most frequently used models in both the groups. The difference in reference sound levels between uncontrolled and controlled groups was 1.50 dB (SD 4.42). The mean SD of the reference sound level determined for devices within the same model was 4.03 dB (95% CI 3.93-4.11). Statistically significant differences were found across models.

Conclusions

Reference sound levels determined in the uncontrolled group are comparable to the values obtained in the controlled group. This validates the use of biological calibration in the uncontrolled group for determining the predefined reference sound level for new devices. Moreover, due to a relatively small deviation of the reference sound level for devices of the same model, it is feasible to conduct hearing screening on devices calibrated with the predefined reference sound level.

The use of telehealth services to facilitate audiological management for children: A scoping review and content analysis

Approximately 32 million children globally present with disabling hearing loss. Despite evidence describing the negative consequences of hearing loss, there is still a lack of hearing screening programmes in South Africa. Audiologists have been exploring the use of information and communication technologies (tele-audiology) to provide services to children and it is currently being evaluated to determine its feasibility.

Aims

We aim to describe tele-audiology services conducted to facilitate audiological management for children in both the rural and urban context and to determine the strengths, challenges and clinical implications of such services.

Methods

A scoping review was conducted by searching for peer-reviewed publications from five databases. Inclusion criteria and search strategies were outlined.

Results

Of the 23 studies that met the inclusion criteria, reliability of automated testing was comparable to conventional testing; however, these studies were based primarily on screening programmes. Eight (35%) of the 23 papers were concordance studies evaluating feasibility and validity of tele-audiology systems when compared with conventional testing, while one study (4%) evaluated a tele-audiology service. A further four studies (17%) evaluated the feasibility of introducing telehealth methods to evaluate middle ear pathology. Tele-auditory brainstem response was investigated in three studies (13%) and another five (22%) used smartphone and/or iPad technology to screen hearing. Only two studies (9%) evaluated the feasibility of providing intervention through telehealth methods. All included studies demonstrated improved access to and coverage of rural areas. Services such as video otoscopy and synchronous (online) hearing testing in remote areas were successfully implemented. Challenges included lack of diagnostic studies, inadequate training of staff and the need to standardize protocols and procedures in order to ensure that tele-audiology services are provided in a standardized and valid manner.

Conclusion

Tele-audiology services are feasible and can be useful in identifying auditory pathology for children in rural and remote areas.

Self-administered hearing loss screening using an interactive, tablet play audiometer with ear bud headphones

BACKGROUND AND OBJECTIVE

The timely diagnosis and treatment of acquired hearing loss in the pediatric population has significant implications for a child's development. Audiological assessment in children, however, carries both technological and logistical challenges. Typically, specialized methods (such as play audiometry) are required to maintain the child's attention and can be resource intensive. These challenges were previously addressed by a novel, calibrated, interactive play audiometer for Apple(®) iOS(®) called "ShoeBOX Audiometry". This device has potential applications for deployment in environments where traditional clinical audiometry is either unavailable or impractical. The objective of this study was to assess the screening capability of the tablet audiometer in an uncontrolled environment using consumer ear-bud headphones.

METHODS

Consecutive patients presenting to the Audiology Clinic at the Children's Hospital of Eastern Ontario (ages 4 and older) were recruited. Participants' hearing was evaluted using the tablet audiometer calibrated to Apple(®) In-Ear headphones. The warble tone thresholds obtained were compared to gold standard measurements taken with a traditional clinical audiometer inside a soundbooth.

RESULTS

80 patients were enrolled. The majority of participants were capable of completing an audiologic assessment using the tablet computer. Due to ambient noise levels outside a soundbooth, thresholds obtained at 500Hz were not consistent with traditional audiometry. Excluding 500Hz threholds, the tablet audiometer demonstrated strong negative predictive value (89.7%) as well as strong sensitivity (91.2%) for hearing loss.

CONCLUSION

Thresholds obtained in an uncontrolled setting are not reflective of diagnostic thresholds due to the uncalibrated nature of the headphones and variability of the setting without a booth. Nevertheless, the tablet audiometer proved to be both a valid and sensitive instrument for unsupervised screening of warble-tone thresholds in children.

Teleaudiometry as a screening method in school children

OBJECTIVE

To compare the efficacy and feasibility of teleaudiometry with that of sweep audiometry in elementary school children, using pure-tone audiometry as the gold standard.

METHODS

A total of 243 students with a mean age of 8.3 years participated in the study. Of these, 118 were boys, and 125 were girls. The following procedures were performed: teleaudiometry screening with software that evaluates hearing at frequencies of 1,000, 2000 and 4000 Hz at 25 dBHL; sweep audiometry screening in an acoustic booth (20 dBHL at the same frequencies); pure-tone audiometry thresholds in an acoustic booth (frequencies of 500, 1000, 2000 and 4000 Hz); and acoustic immittance measurements.

RESULTS

The diagnostic capacities of the teleaudiometry/sweep audiometry screening methods were as follows: sensitivity  ϝ  58%/65%; specificity  ϝ  86%/99%; positive predictive value  ϝ  51%/91%; negative predictive value  ϝ  89%/92%; and accuracy  ϝ  81%/92%. Teleaudiometry and sweep audiometry showed moderate agreement. Furthermore, the use of these methods in series with immittance testing improved the specificity, whereas parallel testing improved the sensitivity.

CONCLUSION

Teleaudiometry was found to be reliable and feasible for screening hearing in school children. Moreover, teleaudiometry is the preferred method for remote areas where specialized personnel and specific equipment are not available, and its use may reduce the costs of hearing screening programs.

Auditory steady-state responses in school-aged children: a pilot study

Background

The use of Auditory Steady-State Responses (ASSRs) for auditory screening in school-aged children, particularly in children who are difficult to test and children with disabilities, has not been explored yet. This pilot study investigated the use of ASSR for auditory screening in school-aged children.

Materials and methods

A cross-sectional pilot study of 23 children aged 9 to 11 with normal-hearing thresholds and seven age-matched children with permanent moderate-to-profound bilateral hearing loss were examined. The tested carrier frequencies were 500, 1,000, 2,000, and 4,000 Hz, and the stimulus was modulated between 77 and 107 Hz. The ASSRs decreased according to the tested intensity levels of 50, 40, and 30 dB sound pressure level (SPL). Sensitivity and specificity were estimated from the responses of the children with normal hearing and those with hearing loss.

Results

For the children with normal hearing, the 2,000-Hz frequency was detected more often in both ears and at all intensity levels compared to the other frequencies. The 500- and 2,000-Hz frequencies resulted in different response patterns in both ears. The time until response detection increased in parallel with amplitude reduction, as expected. The overall time required for the test was 15 minutes, including the time spent in volunteer preparation. The sensitivity was 97% for the three intensities, and the best specificity value was 100%, which was observed at 50 dB.

Discussion

The response analysis indicated that a screening protocol for school-aged children could include 1,000, 2,000, and 4,000 Hz and that the recording of ASSRs was highly sensitive to internal and external factors. Fifty dB SPL should be considered a cut-off criterion for screening purposes because this was the intensity level with a sensitivity of 97% and a specificity of 100%.

Conclusion

The use of ASSRs might be particularly useful in school-aged children who have difficulty performing subjective hearing tests. The sensitivity and specificity data suggested that the use of ASSRs was feasible as an auditory screening tool. In order to determine a protocol for screening, future studies should include a larger sample and children with mild hearing loss.

Automated hearing screening for children: A pilot study in China

OBJECTIVE

To establish the reliability and validity of an automated hearing screening test system for children.

DESIGN

Cross-sectional within a comparative study of subjects.

STUDY SAMPLE

Subjects were 325 first-grade and second-grade children (6-10 years old) from primary schools in Shenzhen, China.

RESULTS

Using the conventional pure-tone screening test with the pass/refer criterion set as 25 dB HL, as the 'gold standard", the sensitivity and specificity of the automated hearing screening test was 0.63 and 0.82, respectively. No specific pattern in the failure rates was observed to relate to the students' grade. There was no statistically significant age effect or gender effect.

CONCLUSIONS

The results suggest that with further improvement in terms of its sensitivity and specificity, it may be feasible to use the automated hearing screening test system to conduct routine school hearing screenings.

Results obtained with a low cost software-based audiometer for hearing screening

Introduction: The implementation of hearing screening programs can be facilitated by reducing operating costs, including the cost of equipment. The Telessaúde (TS) audiometer is a low-cost, software-based, and easy-to-use piece of equipment for conducting audiometric screening.

Aim: To evaluate the TS audiometer for conducting audiometric screening.

Methods: A prospective randomized study was performed. Sixty subjects, divided into those who did not have (group A, n = 30) and those who had otologic complaints (group B, n = 30), underwent audiometric screening with conventional and TS audiometers in a randomized order. Pure tones at 25 dB HL were presented at frequencies of 500, 1000, 2000, and 4000 Hz. A “fail” result was considered when the individual failed to respond to at least one of the stimuli. Pure-tone audiometry was also performed on all participants. The concordance of the results of screening with both audiometers was evaluated. The sensitivity, specificity, and positive and negative predictive values of screening with the TS audiometer were calculated.

Results: For group A, 100% of the ears tested passed the screening. For group B, “pass” results were obtained in 34.2% (TS) and 38.3% (conventional) of the ears tested. The agreement between procedures (TS vs. conventional) ranged from 93% to 98%. For group B, screening with the TS audiometer showed 95.5% sensitivity, 90.4% sensitivity, and positive and negative predictive values equal to 94.9% and 91.5%, respectively.

Conclusions: The results of the TS audiometer were similar to those obtained with the conventional audiometer, indicating that the TS audiometer can be used for audiometric screening.

Hearing screening for school children: utility of noise-cancelling headphones

BACKGROUND

Excessive ambient noise in school settings is a major concern for school hearing screening as it typically masks pure tone test stimuli (particularly 500 Hz and below). This results in false positive findings and subsequent unnecessary follow-up. With advances in technology, noise-cancelling headphones have been developed that reduce low frequency noise by superimposing an anti-phase signal onto the primary noise. This research study examined the utility of noise-cancelling headphone technology in a school hearing screening environment.

METHODS

The present study compared the audiometric screening results obtained from two air-conduction transducers-Sennheiser PXC450 noise-cancelling circumaural headphones (NC headphones) and conventional TDH-39 supra-aural earphones. Pure-tone hearing screening results (500 Hz to 4000 Hz, at 30 dB HL and 25 dB HL) were obtained from 232 school children, aged 6 to 8 years, in four Hong Kong primary schools.

RESULTS

Screening outcomes revealed significant differences in referral rates between TDH-39 earphones and NC headphones for both 30 dB HL and 25 dB HL criteria, regardless of the inclusion or exclusion of 500 Hz results. The kappa observed agreement (OA) showed that at both screening intensities, the transducers' referral agreement value for the 500 Hz inclusion group was smaller than for the 500 Hz exclusion group. Individual frequency analysis showed that the two transducers screened similarly at 1000 Hz and 2000 Hz at 25 dB HL, as well as at both 30 dB HL and 25 dB HL screening levels for 4000 Hz. Statistically significant differences were found for 500 Hz at 30 dB HL and at 25 dB HL, and for 1000 Hz and 2000 Hz at 30 dB HL. OA for individual frequencies showed weaker intra-frequency agreement between the two transducers at 500 Hz at both intensity criterion levels than at higher frequencies.

CONCLUSIONS

NC headphones screening results differed from those obtained from TDH-39 earphones, with lower referral rates at 500 Hz, particularly at the 25 dB HL criterion level. Therefore, NC headphones may be able to operate at lower screening intensities and subsequently increase pure-tone screening test sensitivity, without compromising specificity. NC headphones show some promise as possible replacements for conventional earphones in school hearing screening programs.

The new age of play audiometry: prospective validation testing of an iPad-based play audiometer

OBJECTIVE

The timely diagnosis of hearing loss in the pediatric population has significant implications for a child's development. However, audiological evaluation in this population poses unique challenges due to difficulties with patient cooperation. Though specialized adaptations exist (such as conditioned play audiometry), these methods can be time consuming and costly. The objective of this study was to validate an iPad-based play audiometer that addresses the shortcomings of existing audiometry.

METHODS

We designed a novel, interactive game for the Apple® iPad® that tests pure tone thresholds. In a prospective, randomized study, the efficacy of this tool was compared to standard play audiometry. 85 consecutive patients presenting to the Audiology Clinic at the Children's Hospital of Eastern Ontario (ages 3 and older) were recruited into this study. Their hearing was evaluated using both tablet and traditional play audiometry.

OUTCOME MEASURE

Warble-tone thresholds obtained by both tablet and traditional audiometry.

RESULTS

The majority of children in this age group were capable of completing an audiologic assessment using the tablet computer. The data demonstrate no statistically significant difference between warble-tone thresholds obtained by tablet and traditional audiometry (p=0.29). Moreover, the tablet audiometer demonstrates strong sensitivity (93.3%), specificity (94.5%) and negative predictive value (98.1%).

CONCLUSION

The tablet audiometer is a valid and sensitive instrument for screening and assessment of warble-tone thresholds in children.

Global and regional hearing impairment prevalence: an analysis of 42 studies in 29 countries

BACKGROUND

Hearing impairment is a leading cause of disease burden, yet population-based studies that measure hearing impairment are rare. We estimate regional and global hearing impairment prevalence from sparse data and calculate corresponding uncertainty intervals.

METHODS

We accessed papers from a published literature review and obtained additional detailed data tabulations from investigators. We estimated the prevalence of hearing impairment by region, sex, age and hearing level using a Bayesian hierarchical model, a method that is effective for sparse data. As the primary objective of modelling was to produce regional and global prevalence estimates, including for those regions with scarce to no data, models were evaluated using cross-validation.

RESULTS

We used data from 42 studies, carried out between 1973 and 2010 in 29 countries. Hearing impairment was positively related to age, male sex and middle- and low-income regions. We estimated that the global prevalence of hearing impairment (defined as an average hearing level of 35 decibels or more in the better ear) in 2008 was 1.4% (95% uncertainty interval 1.0-2.2%) for children aged 5-14 years, 9.8% (7.7-13.2%) for females >15 years of age and 12.2% (9.7-16.2%) for males >15 years of age. The model exhibited good external validity in the cross-validation analysis, with 87% of survey estimates falling within our final model's 95% uncertainty intervals.

CONCLUSION

Our results suggest that the prevalence of child and adult hearing impairment is substantially higher in middle- and low-income countries than in high-income countries, demonstrating the global need for attention to hearing impairment.

Innovative technology in hearing instruments: matching needs in the developing world

Hearing instrument technology research is almost entirely focused on the projected needs of the consumer market in the developed world. However, two thirds of the world's population with hearing impairment live in developing countries and this proportion will increase in future, given present demographic trends. In developing regions, amplification and other hearing health needs may differ from those in industrialized nations, for cultural, health, or economic reasons. World Health Organization estimates indicate that at present only a small percentage of individuals in developing countries who are in need of amplification have access to hearing aid provision. New technologies, such as trainable hearing aids, advanced noise reduction algorithms, feedback reduction circuitry, nano coatings for hearing aid components, and innovative power options, may offer considerable potential benefits, both for individuals with hearing impairment in developing countries and for those who provide hearing health care services in these regions. This article considers the possible supporting role of innovative hearing instrument technologies in the provision of affordable hearing health care services in developing countries and highlights the need for research that considers the requirements of the majority of the world population in need of hearing instrument provision.

A comparison of audiometric and objective methods in hearing screening of school children. A preliminary study

OBJECTIVE

In newborn hearing screening, one exclusively applies objective hearing testing methods--based on evoked potentials and/or on otoacoustic emissions. However, when testing school children, one can consider both audiometric and electrophysiological methods. The choice of methods is determined by the aims of the program. If one wants to detect conductive hearing losses, impedance audiometry seems to be the method of choice.

METHODS

The aim of this study was to compare test performance measures from audiometric and objective methods (OAEs and impedance audiometry), in the hearing screening of school children. Screening protocols were applied on a group of 190 children of about 12 years of age (6th grade of primary school).

RESULTS

For a single application of a screening procedure, the best performance was observed in the automated four-tone audiometry, followed by the tympanometry and the TEOAE-based procedures. Screening performance was enhanced using a combination of automated and impedance audiometry. A four-tone audiometry test combined with tympanometry gives a sensitivity of 65%, and the PPV of 46%, which are reasonable values, acceptable for practical use. The use of a TEOAE protocol degrades the overall performance of screening.

CONCLUSIONS

Screening of school children is feasible with a combination of automated audiometry and tympanometry with time requirements equal to 3 min per subject.