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BACKGROUND: The aim of this study was to evaluate the state of implementation of the Universal Newborn Hearing Screening Programs in Italy and to determine the effect that an ad hoc legislation may have on the percentage of infants screened for detection of hearing impairment in nurseries. MATERIAL AND METHODS: Italian Newborn Hearing Screening data were obtained during four national surveys (years 2003, 2006, 2008, and 2011). The screening rates obtained by the Regions which adopted or did not adopt a legislation to increase the newborns' coverage were compared. RESULTS: In 2011, the average coverage rate was 78.3%, but in 12 out of 20 Regions it exceeded 95%. Coverage rate was greater in Regions that implemented an ad hoc legislation compared to Regions that did not. As a matter of fact, Regions which passed the legislation screened more than 95% of infants, whereas Regions without legislation reported a mean screening rate of nearly 67% of newborns. CONCLUSION: Current results seem to confirm that a specific legislation might have a decisive effect on the increase of rate of coverage of newborn hearing screenings.

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PURPOSE: To screen hearing and evaluate outcomes in community-dwelling older adults. METHOD: Three thousand and twenty-five adults responded to an invitation to be screened by questionnaire, otoscopy, and pure-tone audiometry. Pure-tone average (PTA) >35 dB HL in the worse ear, unilateral hearing loss, or otoscopic findings were the criteria for referral for services. A questionnaire related to compliance with referral recommendations was completed by telephone interview for 160 randomly selected participants after 1-2 years from referral. RESULTS: The referral rate for audiologic/hearing aid evaluation was 46%, and referral for cerumen removal/medical evaluation was 17%. Of the people referred for audiologic/hearing aid evaluation, 18% tried a hearing aid; 2 years later, 11% were using a hearing aid. Screening recommendations affected participants' decision to seek help. Study participants stated that the screening was helpful, it should be offered to everybody, and they would participate in future screenings. CONCLUSION: Although adult hearing screening offered timely identification of hearing loss for adults seeking help, follow-up with hearing aid treatment was low.

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The SUN-test (Speech Understanding in Noise) is a speech-in-noise test to screen adults and older adults for hearing disability. The SUN-test consists in a short list of intervocalic consonants (VCV, vowel-consonant-vowel) in noise that are presented in a three-alternatives forced choice (3AFC) paradigm by means of a touch-screen interface. Based on the number of stimuli correctly identified, the tested subject gets one of three possible test outcomes: no listening difficulties, a hearing check would be advisable, or a hearing check is recommended. This paper reviews the main results obtained with the SUN-test in the Italian language in a population of nearly 1,300 adults and older adults with varying degrees of audiometric thresholds and audio-metric configurations, tested both in low and in high ambient noise settings. Results obtained in the tested population revealed that the outcomes of the SUN-test were in line with the outcomes of pure-tone testing, and that the test performance was similar both in low and in high ambient noise (up to 65 dB A). Results obtained with the SUN-test were not biased by the age of the subject because the performance of younger and older subjects in the test was similar. The mean duration of the SUN-test was nearly 40 s/ear, and was lower than 1 minute per ear even in subjects older than 80 years so that both ears could be tested, on average, in 2 minutes. The SUN-test was considered easy or slightly difficult by nearly 90% of subjects; test duration was judged short or fair by nearly 95% of subjects, and the overall evaluation of the test was pleasant, or neutral, in more than 90% of subjects. Overall, results of this study indicated that the SUN-test might be feasible for application in adult hearing screening. The test is fast, easy, self convincing, and reflects differences in hearing sensitivity between the tested subjects. The outcomes of the SUN-test were not influenced by the noise level in the test room (up to 65 dB A) indicating that the test, as such, might be feasible to screen adults and older adults both in clinical and in non clinical settings, such as convenient care clinics, hearing aid providers, or pharmacies, where the ambient noise is, typically, not controlled.

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The development of hearing diagnosis methods and hearing screening methods are not isolated phenomena: they are intimately related to changes in the cultural background and to advances in fields of medicine and engineering. In the recent years, there has been a rapid evolution in the development of fast, easy and reliable techniques for low-cost hearing screening initiatives. Since adults and elderly people typically experience a reduced hearing ability in challenging listening situations [e.g., in background noise, in reverberation, or with competing speech (Pichora-Fuller & Souza, 2003)], these newly developed screening tests mainly rely on the recognition of speech stimuli in noise, so that the real experienced listening difficulties can be effectively targeted (Killion & Niquette, 2000). New tests based on the recognition of speech in noise are being developed on portable, battery-operated devices (see, for example, Paglialonga et al., 2011), or distributed diffusely using information and communication technologies. The evolutions of e-Health and telemedicine have shifted focus from patients coming to the hearing clinic for hearing health evaluation towards the possibility of evaluating the hearing status remotely at home. So far, two ways of distributing the hearing test have primarily been used: ordinary telephone networks (excluding mobile networks) and the internet. When using the telephone network for hearing screening, the predominantly test is a speech-in-noise test often referred to as the digit triplet test where the subjects hearing status is evaluated as the speech-to-noise threshold for spoken digits. This test is today available in some ten countries in Europe, North America and Australia. The use of internet as testing platform allows several different types of hearing assessment tests such as questionnaires, different types of speech in noise tests, temporal gap detection, sound localization (minimum audible angle), and spectral (un)masking tests. Also, the use of the internet allows audiovisual presentations as well as visual interaction and cues in the tests for a more ecological approach. Even if several new and novel approaches for hearing assessment using the internet are surfacing, the validated tests are based on questionnaires or speech-in-noise. Although the internet allows for a broader flora of pure auditory and audiovisual tests for hearing health assessment, calibration problems such as timing uncertainty, output levels and modes of presentation (speakers or earphones) limits the usability at present.

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A series of pilot initiatives of adult hearing screening programs were organized in eight large and small-size cities in Italy in the past two years. The screening initiatives were held in public places, supermarkets, drugstores, and in some universities of the third age, and involved an overall population of 2,278 screened subjects with age ranging from 13 to 93 years. Three different screening tests were used to assess hearing ability in the participants, i.e.: screening pure tone audiometry (PTA), an automated speech-in-noise screening test (the SUN-test), and a screening questionnaire of self-perceived hearing handicap (the HHIE-S). This paper describes the organization and management of these screening initiatives and reviews the main results obtained in the screened population, using the three different screening tests. Results obtained in these pilot initiatives showed that screening adults for hearing problems might be feasible, on a local level, in non clinical settings and can be performed quite easily with the support of local coordinators and partners, such as associations or local authorities. It is recognized that further initiatives and studies will have to be performed to better define the key aspects related to the organization and management of adult hearing screening programs, either at a local, regional, or national level.

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OBJECTIVE: To assess whether different compact disk recording protocols, used to prepare speech test material, affect the reliability and comparability of speech audiometry testing. MATERIAL AND METHODS: We conducted acoustic analysis of compact disks used in clinical practice, to determine whether speech material had been recorded using similar procedures. To assess the impact of different recording procedures on speech test outcomes, normal hearing subjects were tested using differently prepared compact disks, and their psychometric curves compared. RESULTS: Acoustic analysis revealed that speech material had been recorded using different protocols. The major difference was the gain between the levels at which the speech material and the calibration signal had been recorded. Although correct calibration of the audiometer was performed for each compact disk before testing, speech recognition thresholds and maximum intelligibility thresholds differed significantly between compact disks (p < 0.05), and were influenced by the gain between the recording level of the speech material and the calibration signal. CONCLUSION: To ensure the reliability and comparability of speech test outcomes obtained using different compact disks, it is recommended to check for possible differences in the recording gains used to prepare the compact disks, and then to compensate for any differences before testing.

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CONCLUSION: Our results suggest a rapid diffusion of newborn hearing screening programs in Italy and indicate that three conditions seem to play a crucial role in the implementation of Universal Newborn Hearing Screening (UNHS) programs: the size (>800 births/year) and location (metropolitan urban areas) of the hospital, and the presence of an audiologist in the UNHS coordinating team. OBJECTIVES: The aim of this paper is to provide data on the degree of implementation and coverage of UNHS programs in Italy. MATERIALS AND METHODS: Data were collected through a Screening Survey Questionnaire that was sent to all birthing hospitals active in Italy in 2006 and was filled in by the chief of the hospital or by the UNHS program coordinator. RESULTS: In Italy UNHS coverage had undergone a steep increase from 29.3% in 2003 (156,048 newborns screened) to 48.4% in 2006 (262,103 screened). The majority of UNHS programs were implemented in the two most economically developed areas, i.e. in the north-west area (79.5%, 108,200 of 136,109 births), and in the north-east area (57.2%, 52,727 of 92,133 births), while a limited diffusion still remains in some areas, typically in the islands (11.3%, 7158 of 63,460 births).

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This study assessed the influence of 'non-ideal' operating conditions typical of cochlear implants (CIs) on the behavior of the wavelet transform (WT) when used to process speech. Particular attention was given to the effect of limited stimulation rate and limited number of channels, typical of CI speech processing, on the performance of the WT. Computer simulations and psychoacoustic recognition tests of WT-processed speech were implemented. The crucial role played by the 'non-ideal' operating conditions on WT speech processing was put in evidence. Psychoacoustic recognition tests proved to be fundamental to evaluate feasibility of WT speech processing for CIs.

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OBJECTIVE: To investigate the effects of a specific aspect of the acquisition procedure, the averaging technique, on the evaluation of click-evoked otoacoustic emissions (CEOAEs) in newborns. DESIGN: CEOAEs were recorded by an Otodynamic ILO88 system from 89 full-term newborns at the third day after delivery. For each ear and in the same test session, CEOAEs were evoked by 75 to 85 dB pSPL acoustic clicks and averaged according to two different modes: the "linear" (classic average) and the "derived" mode, which allows the cancellation of linear behaving components (such as acoustic artifacts). All examined ears had a normal auditory function as assessed by conventional ABR between the ages of 2 and 4 mo. CEOAEs obtained by both averaging techniques were compared on the basis of several quantitative parameters: the waveform similarity; the levels of signal and noise and the inter-test reproducibility of the broadband response and of four different frequency bands centered at 1.6, 2.4, 3.2, and 4 kHz; the amplitude as a function of time; the test time. To eliminate the contribution of the stimulus artifact, linear CEOAEs were windowed 6 to 20 msec, whereas derived emissions were windowed using the default ILO88 window (2.5 to 20 msec). Additionally, CEOAEs were classified as "pass" or "fail" accordingly to screening criteria used in the daily clinical practice. RESULTS: Linear and derived emissions had very similar wave shapes and no time shifts during the first 12.5 msec. On the contrary, clear differences in the waveforms and time shifts were observed at longer latencies. The use of both averaging techniques resulted in identical CEOAE levels for both the broadband response and for the first two tested frequencies. For the last two frequencies, emission levels were lower when averaged with the linear technique owing to the use of the time window 6 to 20 msec, which reduces the amplitudes of high-frequency components. The residual noise in derived traces is 6 dB higher than that from linear traces. Also, derived CEOAEs had a lower inter-test reproducibility in both the broadband compound emission and in the four frequency bands examined here. The greatest difference in reproducibility was observed at the lowest band (1.2 to 2 kHz). Scoring of emissions was influenced by the averaging technique: 14% CEOAEs obtained with linear averaging and scored as passes were classified as fails when averaged with the derived mode. Moreover, if a CEOAE was scored as pass when using the derived technique, it also was scored as pass when using linear averaging. The increased number of false positives most likely was due to the higher noise floor/lower signal to noise ratio (SNR) of CEOAEs obtained with the derived technique. CONCLUSIONS: In the tested newborns and at the levels of stimulation used in this study, the emissions obtained with the derived technique were noisier than those obtained with the linear technique, this being intrinsically due to the type of averaging. Therefore, screening criteria based on the evaluation of the SNR (or similar parameters) could be influenced by the type of averaging used during the acquisition.

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This paper addresses the quantitative investigation of the contribution of spontaneous (SOAE) to click-evoked (TEOAE) otoacoustic emissions in newborns. The hypothesis was that a weighted linear combination of the spontaneous peaks is strongly similar to the corresponding click-evoked emissions. After identification of the main spontaneous peaks for each subject, a best fit procedure was applied to find the amplitude and phase of each spontaneous tone in the weighted summation. The comparison of the weighted signal (SpTEOAE) with the actual click-evoked response (TEOAE) from the same subject was performed, obtaining correlation coefficient higher than 50% in more than 100 ears over 132.

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Click-evoked otoacoustic emissions (CEOAEs) of full-term babies were considered. By means of the wavelet transform, each CEOAE was decomposed into frequency bands. The rms amplitude and test-retest correlation were computed from these bands. The results indicated that both the amplitude and correlation were not invariant with time but reached a maximum in specific time windows, depending on the frequency of the component. For all components, the correlation was greatly decreased for latencies > 12.5 ms. As a result, comparison between the performance of the default ILO 88 window (2.5-20 ms) and the 2.5-12.5 ms window showed that for all frequencies in the 1.5-6 kHz range there was a statistically significant improvement in the correlation.

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Since 1997 a hospital-based universal hearing screening programme (Milan Programme) has been carried out at the Neurophysiopathology Unit of the Mangiagalli Clinic in Milan, for the early identification of hearing loss in neonates (5650 well babies, 749 newborns from the Neonatal Pathology Unit (NPU) without risk for hearing loss and 118 newborns at risk for hearing loss). As a result, considering the well baby population, three pathological neonates (one profound bilateral and two unilateral hearing loss) were identified. Three additional cases were found among the NPU newborns, whereas 16 cases with bilateral and 11 with unilateral hearing loss were found among the at-risk babies.

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Scoring of click-evoked otoacoustic emissions (CEOAEs) is typically achieved by the evaluation of the reproducibility of the whole emission and/or within narrow bands. Screening outcomes are influenced not only by the specific combination of the subdivision scheme (i.e., the number, position, and bandwidth of the narrow bands) and the threshold used to determine pass and refer, but also by the accuracy with which the reproducibility is estimated. This study was designed to examine what factors affect the accuracy of the reproducibility estimate and how the accuracy of the reproducibility estimate together with the choice of the subdivision scheme/thresholds affect CEOAE scoring. Simulations with real CEOAEs corrupted with synthesized noise indicated that the reproducibility estimate is influenced by time-windowing and band-pass filtering: the longer the time-window or the broader the bandwidth of the filter, the more accurate the estimate. Quantitative figures on numerical scoring were given in terms of the referral rate and were derived from CEOAEs recorded in a clinical environment from more than 3400 newborns. The narrow bands were extracted according to 12 different subdivision schemes covering the 1.5-4-kHz range. The referral rate was found to depend on the subdivision scheme being used: (i) the worst results were obtained considering four narrow bands at 1.6-2.4-3.2-4 kHz; (ii) the best results were obtained considering two narrow bands at 2.25 and 3.75 kHz; (iii) bandwidths greater than 1 kHz resulted in the lowest referral rates. Also, scoring based on the extraction of four narrow bands produced the most unstable results, i.e., a small change in the threshold might cause even a great change in the referral rate.

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Previous studies have shown that the effect of contralateral acoustic stimulation (CAS) on ipsilateral evoked otoacoustic emissions (EOAE) depends somewhat upon the spectrum of the eliciting stimulus. The latency of the EOAE, however, is itself frequency-dependent. Consequently, two general ways of analyzing the effects of CAS may be considered: by frequency band or by temporal segment. In this study, we analyzed the effects of CAS both ways in the same subjects, essentially simultaneously. The frequency analysis of the EOAE derived from the wavelet transform (WT). The WT is known to provide a robust approach to the analysis of non-stationary signals and was anticipated to avoid possible time-frequency confounds of the cochlear mechanical system. For comparison, a more basic analysis - using a temporal moving window - was employed. The results largely support earlier findings and confirm that in humans the greatest suppression of EOAEs by CAS is obtained for lower frequency and/or longer latency EOAE components. Despite expectations for the WT analysis, the more basic, temporal, analysis tended to yield the clearer results.

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Click evoked otoacoustic emissions (CEOAEs), pure-tone audiograms (PTAs), and Bekesy sweep frequency audiograms were recorded from 15 ears of 11 subjects with noise-induced hearing loss. For all ears, hearing threshold levels > or = 30 dB HL were found at the high frequencies. The aims of the study were to examine whether the decomposition of CEOAEs into narrow band components could identify hearing loss in a frequency-specific manner and to what extent audiometric thresholds could be predicted. CEOAEs were parcelled into 0.5-kHz-wide components by means of the wavelet transform. Reproducibility of CEOAE components was compared with audiometric threshold at corresponding frequencies. A general trend of low reproducibility for increasing audiometric thresholds was found. A reproducibility value of 60 per cent was found to best separate normal and elevated thresholds. The presence of a CEOAE component at a given frequency was always associated with audiometric thresholds < or = 20-25 dB HL. On the other hand, the absence of a component was equally associated either with normal or abnormal hearing levels. Large inter-subject variability was observed. A weak linear relationship was found between reproducibility and audiometric thresholds at corresponding frequencies, indicating that analysis of narrow band CEOAE components is valuable for separating normal from hearing-impaired ears but cannot replace the audiogram.

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The objective of this study was to investigate the effects of time-windowing on click evoked otoacoustic emissions (CEOAEs); 466 CEOAEs from full-term babies were considered. Data were acquired according to the default ILO88 response window (2.5-20 ms). Because CEOAEs are time-varying signals, each emission was analysed by means of the wavelet transform (WT), a technique which allows a simultaneous representation of the time and frequency features of a signal. By means of the WT it was possible to extract the temporal pattern of the elementary frequency components of the compound emissions. The effects of time-windowing were evaluated on each single emission component: rms and correlation values were computed from six 2.5-ms long time windows in the 2.5-17.5 ms range. Results indicated that both rms and correlation were not constant with time but reached a maximum in specific time-windows, depending on the frequency of the component. For low-frequency components, the correlation typically had a maximum in the interval 10-12.5 ms, whereas high-frequency components had a maximum around 5 ms. Above 12.5 ms, the correlation was greatly decreased for all frequency components. As a result, the comparison between the performance of the default ILO88 window (2.5-20 ms) and the window 2.5-12.5 ms showed that for all frequencies in the 1.5-6 kHz range there was a statistically significant improvement in the correlation. No improvement was observed for frequencies below 1.5 kHz because of their contamination by the residual background noise.

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Human excitable cells can be stimulated noninvasively with externally applied time-varying electromagnetic fields. The stimulation can be achieved either by directly driving current into the tissue (electrical stimulation) or by means of electro-magnetic induction (magnetic stimulation). While the electrical stimulation of the peripheral neuromuscular system has many beneficial applications, peripheral magnetic stimulation has so far only a few. This paper analyzes theoretically the use of multiple magnetic stimulation coils to better control the excitation and also to eventually mimic electrical stimulation. Multiple coils allow electronic spatial adjustment of the shape and location of the stimulus without moving the coils. The new properties may enable unforeseen uses for peripheral magnetic stimulation, e.g., in rehabilitation of patients with neuromuscular impairment.

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This paper investigated the performance of an optimal bandpass filtering technique to effectively identify click evoked otoacoustic emissions in neonates. The frequency response of the filter was optimized by maximizing the correlation coefficient between two replicate recordings (reproducibility). The optimal cut-off frequencies were also set by controlling the maximum energy loss after filtering to stop the crucial response contents being filtered along with the noise. As an additional constraint, the cut-off frequencies were forced to be outside the range of 1.6 to 4.2 kHz to avoid (in a response identification task) the spontaneous otoacoustic emissions from polarizing the cut-offs and thereby filtering fundamental frequency components, thus leading to an erroneous response classification. The best performance of the optimal filter in terms of increasing the post-filtering reproducibility was obtained when the procedure was applied to recordings whose reproducibility before filtering ranged between 60 and 80 per cent, i.e. for responses classified in most cases as partial pass.

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