Maternal and Neonatal Vulnerabilities Associated with Abnormal Outcomes in Newborn Hearing Screening: A Focus on Adolescent Mothers.

After completing this article, readers should be able to: A number of authors suggest that the critical period for development of the auditory system and speech commences in the first 6 months of life and continues through 2 years of age. Specific linguistic experience in the first 6 months of life, before meaningful speech begins, affects infants' perception of speech sounds and their capacity to learn. Moderate-to-severe hearing impairment in the first year of life is believed to compromise speech and language acquisition as well as cognitive and social development. Mild or unilateral hearing deficits also are considered to affect language development and behavior of children. Early intervention (following detection of hearing impairment in those younger than 3 months of age) reduces the age for access to effective medical and habilitative intervention for many infants. Intervention for those younger than 6 months of age also is believed by many to improve speech and language development and cognitive outcomes, diminishing the need for special education and improving quality of life. The evidence for these effects currently is limited in quantity and quality; most studies are retrospective and have significant limitations.The prevalence of moderate through profound hearing impairment‡ in newborns, including both sensorineural (SNHL) and conductive hearing loss (CHL), is in the range of 1 to 3/1,000. Previously published reports are believed to reflect an underestimate of the true prevalence. If infants who have mild SNHL are included, the prevalence would at least double. Furthermore, the prevalence of hearing impairment is increased substantially in newborns who have specific risk indicators (Table 1).Universal newborn hearing screening (UNHS) programs are mandated in at least 32 states in the United States and are being initiated in 20 health districts in the United Kingdom. Prior to these developments, the average age of identification of hearing impairment was about 30 months, with individual cases being diagnosed at a much later age. In addition, children who had mild or moderate hearing losses frequently were not identified until school age. Infants may be referred for testing when a risk indicator for hearing impairment is present (Tables 1 and 2) or if parents, health workers, or other caregivers suspect a hearing deficit. However, it is widely reported that targeted high-risk screening can identify at best about 50% of children who have significant prelingual hearing impairment.A recent systematic review of the evidence supporting UNHS has concluded that modern screening tests for hearing impairment can improve identification of newborns who have permanent hearing impairment, but the efficacy of UNHS to improve long-term language outcomes remains uncertain. That review formed the basis for a recent rating by the United States Preventive Services Task Force of the evidence for effectiveness of UNHS programs as "inconclusive." The review identifies some important gaps and deficiencies in current knowledge about newborn hearing screening, and it is helpful in identifying a research agenda to place screening programs on a more evidentially secure footing. The findings of the review reflect a narrow focus on the scientific quality of evidence relating to specific questions. Such reviews are useful, but they do not encompass a broader picture of poor current identification and a substantial current burden of unidentified and unmanaged hearing disorders in infancy. The review also does not reflect the values that society may place on improvements in early identification, audiologic evaluation, information to parents, access to medical interventions, ability to hear, and other interventions designed to improve communication skills in infancy. These broader considerations are beyond the scope of pure evidence review, but they are within the purview of several multidisciplinary position statements that have been developed nationally and internationally in recent years that generally endorse UNHS.The gold standard for assessing hearing deficit in infants older than 6 months of age comprises behavioral tests that rely on operant conditioning, such as visual reinforcement audiometry (VRA). This involves testing an infant's response to specific tones projected within a soundproof room from different directions. When performed correctly, VRA can yield accurate audiometric thresholds in children as young as 6 months of age who have normal neurologic development. However, in younger infants and in those who have developmental delay or certain physical disabilities, behavioral tests of any type are unreliable and have a low specificity.The auditory brainstem response (ABR) is the only test of auditory function accepted as a proxy gold standard for assessment of hearing sensitivity in newborns and infants. The ABR is an electrical waveform (an evoked potential) generated by neuronal activity in the auditory nerve and brainstem pathways following a transient sound such as a click. Its registration (via skin electrodes, electroencephalographic amplifiers, and computer averaging) does not require a behavioral response. The intensity and rate of stimulation primarily determine the response size, latency, and morphology. The presence of a detectable ABR is considered a proxy for perception of sound. The lowest stimulus level that evokes a detectable ABR is an estimator of the true perceptual threshold for various sounds. There is a high correlation between hearing impairment in infants and alteration in the ABR pattern. Overall, ABR testing provides a reasonable evaluation of thresholds over a broad range of hearing impairments and permits differentiation between CHL and SNHL. Many studies have demonstrated that the click ABR in early infancy is a good predictor of pure tone auditory thresholds in the 2,000 to 4,000 Hz range, although a more technically correct interpretation is that the ABR reflects the best pure tone threshold in the range of 500 to 4,000 Hz. Skill and experience are required for valid and efficient ABR testing and interpretation of results.Current screening technologies include: automated auditory brainstem response (AABR), transient evoked otoacoustic emissions (TEOAE), and distortion product otoacoustic emissions (DPOAE). The screening device objectively and automatically detects the response to sound (either an evoked potential or an otoacoustic emission), and the outcome is designated as a "pass" or "fail" ("refer") by the automated analyser. In the screening mode, the three screening methods indicate presence or absence of a response at a specific stimulus level; they neither quantitatively estimate the severity of the hearing impairment nor distinguish conductive from sensorineural hearing impairment.The AABR is a modification of conventional ABR testing, usually involving a single stimulus level and automated response detection. Typically, a series of click stimuli at a level of approximately 30 to 40 dB nHL (normal hearing level is the threshold of audibility of the clicks in normal young adult listeners) is delivered. The electrical signals from at least three or four electrodes on the head are amplified and computer-processed in an attempt to extract the minute ABR from the ongoing electromyogenic and electroencephalic activity that is unrelated to the stimulus. The key technique is averaging of the waveforms recorded after several thousand stimuli, delivered very rapidly. The resultant waveform is tested statistically to determine whether it is a genuine evoked response or merely random electrical noise.Using statistical response detection eliminates the need for waveform interpretation by a highly trained professional. This is important both to reduce screening manpower costs and to increase the accuracy and consistency of response detection. A variety of automated ABR screening instruments is commercially available.TEOAE are elicited by click stimuli delivered by a probe transducer in the external ear canal. The emission or "echo" from the inner ear is a very faint sound with a complex waveform that is recorded by a sensitive, miniature microphone in an external ear probe assembly. Some method of signal enhancement, such as signal averaging, is necessary to distinguish the otoacoustic emissions (OAE) from ambient sound.TEOAE presence implies integrity of sound transmission through the outer and middle ear structures and functional integrity of the outer hair cells, which are the primary sensory transducers with the organ of Corti in the cochlea and are believed to be the site of emissions generation. Low ambient noise level, a clear external auditory meatus and middle ear, probe stability, appropriate choice of stimulus intensity, later postnatal testing, and cochlear maturation all improve the specificity of TEOAE screening. Because the original patent on the TEOAE method only expired recently, the variety of commercially available TEOAE screening devices is limited, although this is changing rapidly.DPOAE are an alternative form of cochlear emission, also having their origin in the outer hair cells of the cochlea. The stimulus is two simultaneous sustained pure tones (primary frequencies of f1 and f2) typically in the 50 to 70 dB intensity range and with a frequency ratio of about 1.22. Under these conditions, a nonlinear stimulus interaction occurs within the cochlea, and a tonal distortion product at a frequency of 2f1-f2 is generated and radiates back to the external ear. Just as for the TEOAE, the DPOAE are detectable in the external meatus. The frequency-specific nature of the DPOAE may provide more precise information than with the TEOAE, but poor recording conditions may result in inaccurate measurements.Any factor that interferes with the registration of a clear ABR or OAE will cause false-positive screening outcomes. The specificity of the AABR, TEOAE, and DPOAE improves when screening takes place at a later postnatal age and with cleaning of the external auditory meatus. This difference is believed to be due to cochlear maturation, clearance of middle ear fluid after the first 48 hours of life, or improved tympanic membrane mobility. Excessive environmental noise also decreases the specificity of TEOAE and DPOAE.There is good evidence that the TEOAE, DPOAE, and AABR are accurate tests for detection of significant hearing impairment in neonates and infants. A two-stage screening protocol tends to yield lower false-positive rates (with specificity >94%) without substantial reduction in sensitivity. Each technology is affected by environmental conditions and the age at which the screen takes place, with the OAE methods affected more than the AABR. There is more variability in the specificity with the TEOAE and DPOAE than with the AABR. That difference is reduced when a two-stage screening procedure is used and the AABR is used for the second stage of the screen. Any of the three screening technologies may be used in a two-stage procedure to detect hearing impairment in newborns. The tests are noninvasive, brief, and inexpensive.Current screening protocols typically employ either a one-, two-, or three-stage screen, with up to two screens prior to discharge from the birth admission, follow-up screening in the community, or both. A higher rate of false-positive findings immediately postnatally (attributed to resolving middle-ear conditions) may be addressed by multistage screening with an outpatient rescreen. Children failing the screening protocol should undergo prompt confirmatory and diagnostic hearing assessment with manual ABR or VRA (preferably including ear-specific and frequency-specific techniques), tympanometry, acoustic reflexes, and other audiologic tests. A possible screening protocol is outlined in the FigureF1.The current American Academy of Pediatrics guidelines suggest universal identification of hearing impairment by 3 months and commencement of intervention by 6 months of age. Because high referral rates result in increased stress on audiologic services and may cause psychological stress on families of those testing positive, a maximum false-positive rate of 3% is widely endorsed and considered feasible for hearing screening programs. A population coverage benchmark of 95% has been proposed, and a target of 100% sensitivity has been suggested. Realistic values will be determined by the sensitivity and specificity of practicable screening protocols and the outcome cost-benefit structure.The accuracy of screening tests may not be identical in high-risk and low-risk groups. Potential sources of variation include different amounts of progressive or early-onset (ie, noncongenital) pathology in the two groups, confounding of behavioral hearing test outcomes by cognitive deficits, and differences in the distribution of hearing impairment for the two groups. Furthermore, it is easier to achieve behaviorally satisfactory test conditions (ideally, a sleeping baby) in low-risk babies, who generally are less distressed.Important practical issues for UNHS programs include follow-up of both children who fail in-hospital screening and those who are not accessed or successfully screened before discharge. Low rates of screening are of concern and are believed to be due to shorter hospital stays and poor compliance for follow-up of first-stage screening failures. For each additional year of experience with screening, most current programs report increasing participation and follow-up of children who fail the screening. However, ongoing surveillance of infants who pass the neonatal screening but are at risk for progressive or early-onset hearing impairment generally is poor. The yield of UNHS programs is limited by hearing impairment possibly being acquired by both pediatric intensive care unit graduates and well babies (targeted or nontargeted screening). A pass in the UNHS program may give parents a false sense of security that their infant has normal hearing and may lessen parental or professional vigilance for detection of acquired hearing loss. Acquired hearing impairment due to both congenital (eg, cytomegalovirus) or acquired infections (eg, meningitis), acquired conductive hearing impairment (due to recurrent otitis media), or auditory neuropathy will not be detected by UNHS programs.There are concerns that a false-positive screen will result in unnecessary parental anxiety, with a negative effect on the parent-child relationship. Questionnaires of parents whose children underwent UNHS did not confirm this concern. The screen was considered to be quick and painless for the infant. UNHS was considered to be a measure of security except in infants who had unilateral or mild deficits that required no intervention. In addition, high false-positive rates may increase the burden on diagnostic services. High-quality screening programs that have a maximum false-positive rate of 4% (after a two-stage screen) should minimize this effect.Overall, UNHS programs have demonstrated earlier identification of hearing impairment, earlier diagnosis, and earlier intervention, whether by hearing aids or other interventions. It is critical that UNHS activities be followed by timely, appropriate, and well-integrated subsequent steps in the overall process that lead to delivery of effective, efficient, culturally sensitive, and family-centered hearing health care. The overall system is commonly referred to as an Early Hearing Detection and Intervention (EHDI) program.In addition, there now is some indirect evidence that early intervention improves speech, language, cognitive ability, and personal-social skills through amplification with hearing aids or cochlear implants or other communication development programs. Evidence is based largely on retrospective data from cohorts that may not be entirely representative of a universal hearing screening program.Infants who are at risk for postnatal hearing loss that may present after neonatal screening should be rescreened periodically. Intervals of about every 3 to 6 months for at least 3 years have been suggested, but such a schedule is likely to prove impractical. For some risk factors, such as perinatal cytomegalovirus infection, there is evidence of continued postnatal expression over even longer periods. Specific postnatal events such as bacterial meningitis or head injury should be followed systematically by hearing screening. The screening technology most practical for widespread use by nonaudiologist personnel is probably automated OAE, either DPOAE or TEOAE, but because of the increased prevalence of hearing impairment in the at-risk group, the use of a more accurate test such as AABR may be indicated. Infants who fail any such screening, whether periodic or driven by a risk event, should receive full audiologic and otologic examination.It is likely that 5% to 10% of newborns manifest one of the risk indicators for progressive or late-onset hearing loss defined by the Joint Committee on Infant Hearing (Tables 1 and 2), so the total amount of screening activity needing to be directed at progressive and late-onset hearing impairment is substantial. The proportion of children who have hearing impairments at 5 years of age that actually are congenital is not yet well understood, and reported ranges vary widely. This is predictable because epidemiologic patterns of postnatal risk and perinatal management practices affect the distribution of impairment.The key practical aspects of screening young infants relate to the behavioral state of the child and to the environmental noise levels. Whether OAE or ABR methods are used, accuracy will be poor if the child is not resting quietly (preferably sleeping). The primary problem associated with OAE is physical movement of the stimulus probe in the ear canal; for the AABR, electromyogenic interference associated with gross body movement may decrease sensitivity. A similar deterioration of specificity is expected if environmental noise levels are too high, and a limit of about 55 dBA (55dB sound pressure level with a so-called "A-weighting" of energy at various frequencies that approximates the sensitivity characteristics of the human ear) has been suggested.The requirement of a sleeping infant means that accurate, objective, physiologic audiometry by OAE or ABR methods is increasingly difficult to obtain in a child older than 6 months of age. If the risk of hearing impairment is substantial, testing under mild sedation or light general anesthesia may be considered. Sedation or anesthesia probably would be used for full, objective diagnostic assessment immediately following screening failure in infants older than about 6 months or in younger infants who are found to be untestable in natural sleep.It is fortunate that behavorial screening by VRA or related methods such as conditioned play audiometry (CPA) is increasingly feasible for many children older than 6 months of age who have no substantive cognitive deficit. The skill and experience required for accurate and consistent VRA and CPA are substantial. Informal office behavioral screening using various kinds of noisemakers and observing behavioral response is notoriously inaccurate and has little if any place in a high-quality system for childhood hearing health care. Definitive audiologic assessment of children who have significant cognitive disabilities can be a long-term challenge that requires careful longitudinal integration of various types of objective, physiologic evidence (otoacoustic emissions, evoked potentials, middle ear muscle reflexes) as well as behavioral data from formal tests and real-world observations.When a child fails an objective screen, one of the first questions is whether the failure is attributable to middle ear disease.One goal of screening children in the age range of 3 to 5 years is to identify preschoolers who may have developed hearing impairment that is likely to interfere with communication and educational development. In the context of an integrated system for EHDI, such impairments are likely to be late-onset, progressive, or adventitious (hearing loss associated with diseases or traumatic events occurring in early childhood such as meningitis or head trauma). Risk indicators include family history, specific infections, trauma, and parent/caregiver or clinician concerns about hearing, speech, language, or developmental delay.Middle ear disorders are common in this age group, and it can be efficient to screen for both hearing loss and middle ear abnormality. If the child is cooperative, OAE screening is feasible and attractive because of its objectivity. The latest devices incorporate both measurement of OAE and otoacoustic immittance capabilities. This allows simultaneous detection of any hearing impairment of at least 30 dB hearing loss (with OAE) and limited differential diagnosis of the type of impairment (conductive or sensorineural).If a skilled tester and facilities are available and the child is cooperative and responsive, many children in this age group can be screened by CPA under earphones. This technique has the advantage of assessing the full perceptual system of a child, whereas objective procedures such as OAE and AABR measure only physiologic correlates of true hearing. Children who cannot perform adequately on CPA may be able to be tested successfully with VRA. It may be useful to conduct both objective and behavioral screening, where feasible, to guard against screening errors. Failure on either screening tool normally should be followed by full audiologic assessment.When a child fails an objective screen, such as an OAE screen, one of the first questions is whether the failure is attributable to middle ear disease. Tympanometry (immittance testing) can be helpful; when results are normal, the index of suspicion for significant SNHL is increased significantly. Full and prompt diagnostic audiologic assessment is indicated. If the tympanometry result is abnormal, there is a substantial likelihood that the screening failure is attributable to middle ear disease. The presence of a sensorineural component is not ruled out by abnormal tympanometric findings.Detailed guidelines for screening protocols for children of various age groups are published in the Joint Committee on Infant Hearing 2000 position statement and the Guidelines for Audiologic Screening developed by the American Speech-Language-Hearing Association (see Suggested Reading).

The Big Screen Difference

Comparison of costs and referral rates of 3 universal newborn hearing screening protocols

having knowledge about the validity of procedures for newborn hearing screening (NHS) is fundamental, once the purpose of these programs is to identify all newborns with hearing loss at an acceptable cost. to estimate the specificity and the false-positive rate of NHS protocols using transient evoked otoacoustic emissions (TEOAE) and automated auditory brainstem response (AABR). participants were 200 newborns who were submitted to a hearing screening test between March and July 2006. Three protocols were analyzed: protocol 1, NHS was carried out in two steps using TEOAE; protocol 2, NHS was carried out in two steps using AABR; and protocol 3, NHS was carried out in one step, using the two procedures - testing with TEOAE followed by a retest with AABR for all the newborns who did not pass the TEOAE testing. although there was no statistically significant difference when comparing the referral rates to audiological diagnosis obtained in protocols using TEOAE and AABR, the protocol using TEOAE referred four times more newborns. Protocol 3 presented the highest referral rate, with a statistically significant difference when compared to protocols 1 and 2. the false-positive rate and consequently specificity were better for the protocol using AABR, followed respectively by the protocol using TEOAE and using both TEOAE and AABR.

Objective To investigate and analyze the rate and reasons of false positive by newborn hearing screening. Methods Transient evoked otoacoustic emission(TEOAE) and automated auditory brainstem response(AABR) were used to examine the hearing of 4 125 live birth newborns of our hospital's maternity department from Mar. 2003 to Dec.2005. TEOAE was used for preliminary hearing screening in 2 days-3 days after birth, and both TEOAE and AABR were used for the secondary hearing screening at 42 days after birth. Diagnostic hearing tests were used to assess the hearing of those who failed the secondary hearing screening in 3 months after birth. They were followed up for more than 1 year. Results All the 4 125 newborns were had the preliminary hearing screening. 3 886 of them were passed, the ratio was 94.21%. 239 infants failed preliminary hearing screening when they underwent the secondary screening at 42 days after birth. 219 of them were passed, 16 of cases who failed secondary screening were diagnosed with hearing loss, the morbidity of 4 125 newborns was 0.13%. The false positive rate was 5.4% and 0.1% of the preliminary screening and the whole process, respectively. Conclusion Although the false positive rate is very low, the number of false positives can not be ignored. It is important to sum up the reasons of the false positive of hearing screening and reduce its rate as possible as we can. Key words: newborn hearing screening; transient evoked otoacoustic emission(TEOAE); automated auditory brainstem response(AABR); false positive

Congenital hearing loss can have a long-term impact on children’s speech and communication abilities. Early detection and intervention of hearing loss are important in newborns. It is well known that there are several risk factors for hearing loss; however, the relationship between these risk factors and hearing screening tests remains uncertain in Iran. Therefore, this study aimed to explore the relationship between hearing loss risk factors and Automated Auditory Brainstem Response (AABR) and Transient-Evoked Otoacoustic Emissions (TEOAEs) within the Iranian context. This retrospective cross-sectional study was conducted on 9622 newborns (4643 females and 4979 males) in Iran. The data related to newborn hearing screening, including gender, the results of initial hearing screening, and hearing loss risk factors, were extracted from newborns’ record files. Data were analyzed using SPSS and a significant level was 0.05%. 190 (3.45%) newborns were referred to the screening. Fourteen newborns were diagnosed with hearing loss (prevalence of hearing loss = 1.45 per 1000) and 9 had one or more risk factors. There was a strong relationship between NICU admission, hyperbilirubinemia, family history of hearing loss, and consanguineous marriage with hearing screening test results (P < 0.05). Among risk factors investigated in this study, hyperbilirubinemia, family history of hearing loss, and intrauterine infections were not significantly correlated with TEOAEs results (P > 0.05). In contrast, they were significantly correlated with AABR results and the lowest OR was for prematurity and the highest for family history of hearing loss. Hyperbilirubinemia, family history of hearing loss, and intrauterine infections were the most significantly correlated risk factors with AABR and family history of hearing loss could be considered as a risk factor that most often leads to AABR failure results in Iran. So, Iranian clinicians, specifically, should ask parents to ask their relatives about any history of hearing loss or other health conditions that may affect their child's health. The findings also provide further evidence supporting the effectiveness of the newborn hearing screening protocols within the Iranian context, which recommend using AABR and TEOAEs tests for infants with risk factors for hearing loss.

Improving universal newborn hearing screening outcomes by conducting it with thyroid screening

To evaluate the costs and performance characteristics associated with the start-up phase of Universal Newborn Hearing Screening Programs, one utilizing automated auditory brainstem response (AABR) and the other using transient evoked otoacoustic emissions (TEOAE). Economic and performance data were collected at the initiation of both screening programs. Data were collected until 1500 newborn infants were screened or until a referral rate for further audiologic evaluation at hospital discharge of less than or equal to 5% was achieved. Data collected included screening pass/fail rates, referral rates and personnel, equipment, and supply utilization. Actual costs of personnel, equipment, and supplies were used. Statistical comparisons of proportions using z-statistic with the one-tailed test and an alpha of 0.01 were made. Screening in the AABR program was performed by neonatal nurses, whereas screening in the TEOAE program was performed by master's level audiologists. The average age at initial screen was 29 hours for TEOAE, and 9.5 hours for AABR. Eighty-four percent of infants was screened within 24 hours in the AABR program, in contrast to 35% in the TEOAE program. Throughout the duration of the study, the referral rate at hospital discharge remained approximately 15% for the TEOAE program. The AABR referral rate began at 8% and was less than 4% at the completion of the study. Pre-discharge total costs for initiating and establishing the programs were US$49,316 for TEOAE and US$47,553 for AABR. Cost per infant screened was US$32.23 and US$33.68, respectively. When post-discharge screening and diagnostic evaluation costs were included, the total cost per infant screened was US$58.07 for TEOAE and US$45.85 for AABR. AABR appears to be the preferred method for universal newborn hearing screening. AABR was associated with the lowest costs, achieved the lowest referral rates at hospital discharge, and had the quickest learning curve to achieve those rates.

Outcomes with OAE and AABR screening in the first 48 h—Implications for newborn hearing screening in developing countries

To investigate the implications of technology choice between automated auditory brainstem response (AABR) and transiently evoked otoacoustic emissions (TEOAE) on service provision for a universal newborn hearing screening (UNHS) program. Over a 4-day period, we offered to perform AABR hearing screening on a cohort of 48 well babies in the maternity unit and outpatient department of our busy district hospital. Those parents that consented were asked to sign a consent form and their babies were then screened using the Natus ALGO Model 2e color newborn hearing screener supplied on loan from Neonatal Perspectives Ltd, Manchester, UK. We recorded the patient age at testing, test duration, results obtained (as a pass/refer) and any problems that we experienced with the screening progress, together with parent or user perceived differences between this technology and the current TEOAE screen. A single user carried out all screening. Having collected the AABR data, we then analyzed the implications of the results in relation to service provision in our hospital, utilizing historical data on TEOAE screening. Forty-four mothers, from 48, consented to having their baby screened by AABR and we were able to achieve a result in all 44 babies that we screened. At the standard test criteria of 35 dBnHL, a total 42 babies passed the initial screen in both ears and 2 referred in a single ear only. The test duration was less than 5 minutes for 36 of 44 babies. Applying these results to a model of UNHS generated a per screen cost of 15.98 Pounds for a two-stage OAE/AABR program and 14.25 Pounds for an AABR-only program. Parents found the AABR test acceptable and we found that being able to discuss the screen and hearing with the parents while the screen was taking place both time-efficient and reassuring to parents. In our experience and using our screening model, the OAE/AABR two-stage approach would have generated 509 infants for second-stage screening (AABR stage) before full audiological follow up and the AABR-only approach would have generated 72 infants for second stage. Testing with the Natus ALGO Model 2e color newborn hearing screener proved to be practical, time-, and cost-efficient. The low initial referral rate would not only save money within our hospital, but serves to keep parental anxiety at a minimum. The high tolerance of ambient noise allowed flexibility in our screening location and timing, improving our ability to screen before discharge. In our setting, the adoption of AABR as our primary screen is more practical and less expensive than TEOAE.

To compare the initial referral rate, the accurate identification rate of congenital hearing loss, and the cost between one step with transient evoked otoacoustic emissions (TEOAEs), two steps with TEOAE and automated auditory brainstem response (AABR), and one step with AABR in newborn hearing screening program. The aim of this study is to compare their efficacy between our three different protocols and to see which one is most cost-effective. From November 1998 to April 2006, 25,588 healthy newborns were screened for hearing loss in Mackay Memorial Hospital, Taipei. In the periods from November 1998 to January 2004, from February 2004 to February 2005, and from March 2005 to April 2006, the screening tools used were TEOAE alone (n = 18,260), TEOAE plus AABR (n = 3,540), and AABR (n = 3,788), respectively. A statistically significant decrease in referral rate was achieved in the group using AABR as screening tools when compared with TEOAE plus AABR and TEOAE alone (0.8 versus 1.6 versus 5.8%). The accurate identification rate of congenital hearing loss was 0.42% in AABR protocol, 0.25% in TEOAE and AABR protocol, and 0.45% in TEOAE protocol, which was not statistically significant. The total direct costs (including predischarge screening and postdischarge follow-up costs) per screening were US $10.04 for the program using TEOAE alone, US $8.60 for TEOAE plus AABR, and US $7.33 for AABR. The intangible cost (parental anxiety) was much higher in the earlier program due to higher referral rate. In the efficacy of the hearing screening program using the one-step TEOAE, two-step TEOAE and AABR, and one-step AABR programs, the latter significantly decreased the referral rate from 5.8, to 1.6, and to 0.8%. No significant difference was noted between their accurate identification rates of congenital hearing loss. The total costs, including expenditures and intangible cost, were much lower in the protocol with AABR due to reduction in false positives.

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

Purpose: The current study aimed to determine the mean ambient noise levels within a risk-based newborn hearing screening (NHS) programme. It further aimed to investigate the relationship between the ambient noise levels and the screening outcome. A descriptive, longitudinal, repeated measures, within-subjects design was employed. Three hundred and twenty-five neonates from two public sector hospitals were enrolled in an NHS programme.Methods: These neonates underwent an initial hearing screening in the wards, and were thereafter booked for a repeat hearing screening which was conducted in an outpatient clinic within the hospital setting. Screening included transient evoked otoacoustic emissions (TEOAEs), distortion product otoacoustic emissions (DPOAEs) and automated auditory brainstem response (AABR). The maximum ambient noise levels were measured and recorded for each screening session. Data related to mean ambient noise levels were analysed using descriptive statistics. The independent samples t-test and the Wilcoxon rank sum test were used to determine the association between the ambient noise levels and screening outcomes.Results: Results indicated that the ambient sound levels were significantly higher for ears which referred, compared to ears which passed.Conclusion: Findings from the current study highlight the need for monitoring of ambient noise levels across all screening contexts, and consideration of the inclusion of sound level measurements when planning for hearing screening programmes, particularly for contexts where environmental adaptations may not be possible.

Prevalence of sensorineural hearing loss is 1-3 per 1,000 newborns. Transient evoked otoacoustic emission (TEOAE) and automated auditory brain stem responses (AABR) are most frequently used methods in newborn hearing screening programmes. The aim of this study was to examine hearing function in newborns with and without risk factors for hearing loss. We investigated accuracy and feasibility of two automated technologies: transient otoacoustic emissions (TEOAE) and auditory brain stem response (AABR) in early detection of hearing loss. In prospective study, 907 newborns were tested on both ears with transient evoked otoacoustic emissions (TEOAE). If results were "refer" we performed automated brain stem response (AABR). Two stage screening protocols were used with two screening technologies (TEOAE, AABR). Results showed screening pass of 86.3% of the newborns in the first protocol and 99.3% in the second. Six (0.7%) newborns had positive screening results for hearing loss. They were referred for additional audolologic tests (otoacoustic emissions, tympanometry, and auditory brain stem response) to confirm or exclude hearing loss. Audiologic examination was performed up to the third month of life. We confirmed unilateral sensorineural hearing loss in two babies. Average test time per ear was 21.3 +/- 19.4 s forTEOAE and 135.3 +/- 67.9 s for AABR. TEOAE, AABR tests are confidential, noninvasive and feasible methods and can help to detect hearing impairment.

Is discordance in TEOAE and AABR outcomes predictable in newborns?