Voice fundamental frequency differences and speech recognition with noise and speech maskers in cochlear implant recipients.

Cochlear implant (CI) recipients are limited in their perception of voice cues, such as the fundamental frequency (F0). This has important consequences for speech recognition when several talkers speak simultaneously. This examination considered the comparison of clear speech and noise-vocoded sentences as maskers. For the speech maskers it could be shown that good CI performers are able to benefit from F0 differences between target and masker. This was due to the fact that a F0 difference of 80 Hz significantly reduced target-masker confusions, an effect that was slightly more pronounced in bimodal than in bilateral users.

Development of the Farsi Hearing in Noise Test.

Objectives: Develop sentences in Farsi for use in the Hearing In Noise Test (HINT); equalise the difficulty of the sentences; form twelve 20-sentence lists; and determine the reliability and norms for these materials.Design: The same study design as used in the development of HINT in other languages was followed. Sentences were sampled from elementary school reading materials. Sentence difficulty was matched by scaling sentence levels. Equivalent sentence lists were formed. Speech reception thresholds were measured under headphones in quiet and in three noise conditions that differed in the spatial locations of the speech and noise sources. Spatial locations were simulated using head-related transfer functions.Study sample: Subjects were 24 adult native speakers of Farsi with pure-tone thresholds ≤25 dB HL at audiometric frequencies from 0.25 to 8.00 kHz.Results: Reliability, the variability of test-retest score differences, was 1.28 dB in quiet and 1.08 dB in noise. Average speech reception thresholds in Quiet = 19.4 dB(A). Average signal/noise ratios at threshold were Noise Front = -5.4 dB, Noise Right = -13.7 dB, and Noise Left = -13.7.Conclusions: The reliability and norms for the Farsi HINT are comparable to those for other languages, enabling comparison of test results across languages.

Evidence-based occupational hearing screening II: validation of a screening methodology using measures of functional hearing ability.

OBJECTIVE: Validate use of the Extended Speech Intelligibility Index (ESII) for prediction of speech intelligibility in non-stationary real-world noise environments. Define a means of using these predictions for objective occupational hearing screening for hearing-critical public safety and law enforcement jobs. DESIGN: Analyses of predicted and measured speech intelligibility in recordings of real-world noise environments were performed in two studies using speech recognition thresholds (SRTs) and intelligibility measures. ESII analyses of the recordings were used to predict intelligibility. Noise recordings were made in prison environments and at US Army facilities for training ground and airborne forces. Speech materials included full bandwidth sentences and bandpass filtered sentences that simulated radio transmissions. STUDY SAMPLE: A total of 22 adults with normal hearing (NH) and 15 with mild-moderate hearing impairment (HI) participated in the two studies. RESULTS: Average intelligibility predictions for individual NH and HI subjects were accurate in both studies (r2 ≥ 0.94). Pooled predictions were slightly less accurate (0.78 ≤ r2 ≤ 0.92). CONCLUSIONS: An individual's SRT and audiogram can accurately predict the likelihood of effective speech communication in noise environments with known ESII characteristics, where essential hearing-critical tasks are performed. These predictions provide an objective means of occupational hearing screening.

[Characteristics, advantages, and limits of matrix tests]. / Eigenschaften, Leistungen und Grenzen von Matrixtests.

BACKGROUND: Deterioration of communication abilities due to hearing problems is particularly relevant in listening situations with noise. Therefore, speech intelligibility tests in noise are required for audiological diagnostics and evaluation of hearing rehabilitation. OBJECTIVE: This study analyzed the characteristics of matrix tests assessing the 50 % speech recognition threshold in noise. What are their advantages and limitations? METHODS: Matrix tests are based on a matrix of 50 words (10 five-word sentences with same grammatical structure). In the standard setting, 20 sentences are presented using an adaptive procedure estimating the individual 50 % speech recognition threshold in noise. At present, matrix tests in 17 different languages are available. RESULTS: A high international comparability of matrix tests exists. The German language matrix test (OLSA, male speaker) has a reference 50 % speech recognition threshold of -7.1 (± 1.1) dB SNR. CONCLUSION: Before using a matrix test for the first time, the test person has to become familiar with the basic speech material using two training lists. Hereafter, matrix tests produce constant results even if repeated many times. Matrix tests are suitable for users of hearing aids and cochlear implants, particularly for assessment of benefit during the fitting process. Matrix tests can be performed in closed form and consequently with non-native listeners, even if the experimenter does not speak the test person's native language. Short versions of matrix tests are available for listeners with a shorter memory span, e.g., children.

International Collegium of Rehabilitative Audiology (ICRA) recommendations for the construction of multilingual speech tests. ICRA Working Group on Multilingual Speech Tests.

OBJECTIVE: To provide guidelines for the development of two types of closed-set speech-perception tests that can be applied and interpreted in the same way across languages. The guidelines cover the digit triplet and the matrix sentence tests that are most commonly used to test speech recognition in noise. They were developed by a working group on Multilingual Speech Tests of the International Collegium of Rehabilitative Audiology (ICRA). DESIGN: The recommendations are based on reviews of existing evaluations of the digit triplet and matrix tests as well as on the research experience of members of the ICRA Working Group. They represent the results of a consensus process. RESULTS: The resulting recommendations deal with: Test design and word selection; Talker characteristics; Audio recording and stimulus preparation; Masking noise; Test administration; and Test validation. CONCLUSIONS: By following these guidelines for the development of any new test of this kind, clinicians and researchers working in any language will be able to perform tests whose results can be compared and combined in cross-language studies.

The word-with-noise test: development, validation and reference values. / Teste de palavras no ruído: desenvolvimento, validação e valores de referência.

PURPOSE: To propose an instrument for assessing speech recognition in the presence of competing noise. To define its application strategy for use in clinical practice. To obtain evidence of criterion validity and present reference values. METHODS: The study was conducted in three stages: Organization of the material comprising the Word-with-Noise Test (Stage 1); Definition of the instrument's application strategy (Stage 2); Investigation of criterion validity and definition of reference values for the test (Stage 3) through the evaluation of 50 normal-hearing adult subjects and 12 subjects with hearing loss. RESULTS: The Word-with-Noise Test consists of lists of monosyllabic and disyllabic words and speech spectrum noise (Stage 1). The application strategy for the test was defined as the determination of the Speech Recognition Threshold with a fixed noise level at 55 dBHL (Stage 2). Regarding criterion validity, the instrument demonstrated adequate ability to distinguish between normal-hearing subjects and subjects with hearing loss (Stage 3). Reference values for the test were established as cut-off points expressed in terms of signal-to-noise ratio: 1.47 dB for the monosyllabic stimulus and -2.02 dB for the disyllabic stimulus. Conclusion: The Word-with-Noise Test proved to be quick to administer and interpret, making it a useful tool in audiological clinical practice. Furthermore, it showed satisfactory evidence of criterion validity, with established reference values.

OBJETIVO: Propor um instrumento para a avaliação do reconhecimento de fala na presença de ruído competitivo. Definir sua estratégia de aplicação, para ser aplicado na rotina clínica. Obter evidências de validade de critério e apresentar seus valores de referência. MÉTODO: Estudo realizado em três etapas: Organização do material que compôs o Teste de Palavras no Ruído (Etapa 1); Definição da estratégia de aplicação do instrumento (Etapa 2); Investigação da validade de critério e definição dos valores de referência para o teste (Etapa 3), por meio da avaliação de 50 sujeitos adultos normo-ouvintes e 12 sujeitos com perda auditiva. RESULTADOS: O Teste de Palavras no Ruído é composto por listas de vocábulos mono e dissilábicos e um ruído com espectro de fala (Etapa 1). Foi definida como estratégia de aplicação do teste, a realização do Limiar de Reconhecimento de Fala com ruído fixo em 55 dBNA (Etapa 2). Quanto à validade de critério, o instrumento apresentou adequada capacidade de distinção entre os sujeitos normo-ouvintes e os sujeitos com perda auditiva (Etapa 3). Foram definidos como valores de referência para o teste, os pontos de corte expressos em relação sinal/ruído de 1,47 dB para o estímulo monossilábico e de -2,02 dB para o dissilábico. CONCLUSÃO: O Teste de Palavras no Ruído demonstrou ser rápido e de fácil aplicação e interpretação dos resultados, podendo ser uma ferramenta útil a ser utilizada na rotina clínica audiológica. Além disso, apresentou evidências satisfatórias de validade de critério, com valores de referência estabelecidos.

An adaptive Australian Sentence Test in Noise (AuSTIN).

OBJECTIVES: The aim of this research is to describe the development of an adaptive Australian Sentence Test in Noise and to validate the test in terms of test-retest reliability and efficiency using data obtained from its clinical application. DESIGN: The relative intelligibility of 1264 Bamford-Kowal-Bench (BKB)-like sentences in the presence of competing four-talker babble was assessed with cochlear implant recipients. Intensity adjustments to the babble segments were made to reduce intersentence variability. Computer software was developed to administer an adaptive speech reception threshold (SRT) test using these adjusted sentence/babble pairs and test-retest SRT data from a separate group of 23 cochlear implant recipients was analyzed, comparing different SRT calculation and test stopping rules. RESULTS: The adjusted sentence/babble pairs were used in clinical studies to obtain an SRT by presenting 32 sentences. Analysis of test-retest pairs of SRT data from 23 recipients indicated that a psychometric fit SRT calculation rule provided better reliability than did the Hearing in Noise Test (HINT) calculation rule, or rules based on mean turns. This rule, using the morpheme correct scores for each sentence, gave a standard deviation for a single SRT of 0.76 dB. Further analyses revealed that the test could be shortened to 20 sentences with an increase of 0.19 dB in variability, while reducing the median test time by approximately 2 min. CONCLUSIONS: This article reports validation data for a new Australian Sentence Test In Noise. When 20 BKB-like sentences are used with a psychometric fit calculation rule, a standard deviation of approximately 1 dB is obtained in approximately 3 min 36 sec.

Envelope following responses elicited by English sentences.

OBJECTIVES: It would be clinically valuable if an electrophysiological validation of hearing aid effectiveness in conveying speech information could be performed when a device is first provided to the individual after electroacoustic verification. This study evaluated envelope following responses (EFRs) elicited by English vowels in a steady state context and in natural sentences. It was the purpose of this study to determine whether EFRs could be detected rapidly enough to be clinically useful. DESIGN: EFRs were elicited using 5 vowels spanning the English vowel space, /i/, /ε/, /æ/, /(Equation is included in full-text article.)/, and /u/. These were presented either as concatenated steady state vowels (total duration 10.04 seconds) or in three 5-word sentences (total duration 11.77 seconds), where each vowel appeared once per sentence. Single-channel electroencephalogram was recorded from vertex (Cz) to the nape of the neck for 190 and 160 repetitions of the steady state vowels and sentences, respectively. The stimuli were presented at 70 dBA SPL. The fundamental frequency (f0) track from the stimuli was used with a Fourier analyzer to estimate the EFRs to each vowel. Noise amplitudes were also calculated at neighboring frequencies. Fifteen normal-hearing subjects who were 20 to 34 years of age participated in the experiment. RESULTS: In the analysis of steady state vowels, the mean response amplitude of /i/ was statistically the largest at 173 nV. The other 4 steady state vowels did not differ in mean response amplitude, which varied between 73 and 106 nV. In the analysis of vowels from the 3 sentences, the largest response amplitudes tended to be for /u/. Mean amplitudes for /u/ were 164, 111, and 140 nV for the words "booed," "food," and "Sue," respectively. The vowel /u/ produced statistically larger responses than /i/, /ε/, and /(Equation is included in full-text article.)/ when grouped across words, whereas other vowels did not differ. Mean response amplitudes for the other vowel categories in the sentences varied between 82 and 105 nV. All subjects showed significant EFRs in response to the words "Bee's" and "booed," but only 9 subjects showed significant EFRs for "pet," "bed," and "Bob." CONCLUSIONS: The authors were readily able to detect significant EFRs elicited by vowels in a steady state context and from 3 natural sentences. These results are promising as an early step in developing a clinical tool for validating that vowel stimuli are at least partially encoded at the level of the auditory brainstem. Future research will require evaluation of the technique with aided listeners, where the natural sentences are expected to be treated as typical speech by hearing aid signal-processing algorithms.

The relationship between high-frequency pure-tone hearing loss, hearing in noise test (HINT) thresholds, and the articulation index.

BACKGROUND: Speech recognition in noise testing has been conducted at least since the 1940s (Dickson et al, 1946). The ability to recognize speech in noise is a distinct function of the auditory system (Plomp, 1978). According to Kochkin (2002), difficulty recognizing speech in noise is the primary complaint of hearing aid users. However, speech recognition in noise testing has not found widespread use in the field of audiology (Mueller, 2003; Strom, 2003; Tannenbaum and Rosenfeld, 1996). The audiogram has been used as the "gold standard" for hearing ability. However, the audiogram is a poor indicator of speech recognition in noise ability. PURPOSE: This study investigates the relationship between pure-tone thresholds, the articulation index, and the ability to recognize speech in quiet and in noise. RESEARCH DESIGN: Pure-tone thresholds were measured for audiometric frequencies 250-6000 Hz. Pure-tone threshold groups were created. These included a normal threshold group and slight, mild, severe, and profound high-frequency pure-tone threshold groups. Speech recognition thresholds in quiet and in noise were obtained using the Hearing in Noise Test (HINT) (Nilsson et al, 1994; Vermiglio, 2008). The articulation index was determined by using Pavlovic's method with pure-tone thresholds (Pavlovic, 1989, 1991). STUDY SAMPLE: Two hundred seventy-eight participants were tested. All participants were native speakers of American English. Sixty-three of the original participants were removed in order to create groups of participants with normal low-frequency pure-tone thresholds and relatively symmetrical high-frequency pure-tone threshold groups. The final set of 215 participants had a mean age of 33 yr with a range of 17-59 yr. DATA COLLECTION AND ANALYSIS: Pure-tone threshold data were collected using the Hughson-Weslake procedure. Speech recognition data were collected using a Windows-based HINT software system. Statistical analyses were conducted using descriptive, correlational, and multivariate analysis of covariance (MANCOVA) statistics. RESULTS: The MANCOVA analysis (where the effect of age was statistically removed) indicated that there were no significant differences in HINT performances between groups of participants with normal audiograms and those groups with slight, mild, moderate, or severe high-frequency hearing losses. With all of the data combined across groups, correlational analyses revealed significant correlations between pure-tone averages and speech recognition in quiet performance. Nonsignificant or significant but weak correlations were found between pure-tone averages and HINT thresholds. CONCLUSIONS: The ability to recognize speech in steady-state noise cannot be predicted from the audiogram. A new classification scheme of hearing impairment based on the audiogram and the speech reception in noise thresholds, as measured with the HINT, may be useful for the characterization of the hearing ability in the global sense. This classification scheme is consistent with Plomp's two aspects of hearing ability (Plomp, 1978).

The AMA method of estimation of hearing disability: a validation study.

OBJECTIVE: To test the assumptions of the 1979 American Medical Association (AMA) method for estimation of hearing disability. DESIGN: One thousand and one patients attending five regional audiology centers competed conventional audiometric testing and the Communication Profile for the Hearing Impaired. A Communication Performance (CP) score calculated from scales of the Communication Profile for the Hearing Impaired served as the gold standard for self-assessed hearing disability. Pure-tone thresholds and word recognition scores (WRSs), and combinations thereof, were compared with the CP scores using correlation and multiple regression analysis. RESULTS: Several different better-ear pure-tone averages (PTAs) correlated reasonably well with self-assessed CP; none were significantly better than the 0.5, 1, 2, and 3 kHz PTA used in the current AMA method. Better-ear to worse-ear weights ranging from 3:1 to 9:1 performed similarly, but none were better than the AMA better-ear weight of 5:1. The AMA method assumes no disability below 25 dB HL and linear growth of disability above this "low fence"; this study showed a similar relationship between PTA and self-assessed hearing disability. There were too few subjects with severe and profound speech-frequency losses to permit validation of the AMA "high fence" of 92 dB HL. Combining pure-tone thresholds and WRSs improved prediction of hearing disability only very slightly. CONCLUSIONS: This study supports the continued use of the 1979 AMA method. Incorporation of WRSs, as typically measured clinically, into methods of estimating hearing disability is not supported because of negligible improvement in accuracy and inability to control exaggeration for speech tests in medical-legal settings.

Development of a Mandarin tone identification test: sensitivity index d' as a performance measure for individual tones.

OBJECTIVE: The aim of this study was to develop comprehensive test material for Mandarin tone identification in noise for a male and a female talker. Additionally, the sensitivity index d' as a measure for the listeners' performance to identify individual tones was evaluated. DESIGN: The study followed a prospective design. STUDY SAMPLE: The complete material comprises 72 loudness-balanced syllables in all 4 Mandarin tones. For a selection of 20 syllables, i.e. 80 test words, performance-versus-intensity functions were measured in spectrally matched noise for 16 normal-hearing participants. RESULTS: The average speech reception thresholds in noise were -12.9 dB for the male and -13.6 dB for the female talker recordings. The corresponding slopes were 8.6%/dB and 7.3%/dB. As a performance measure for individual tones, the proportion of correct responses to specific tones was substantially contaminated by response bias. The sensitivity index d', calculated according to detection theory, provided reasonable and unbiased performance versus intensity functions. CONCLUSIONS: The results firstly indicate that the material is homogenous enough for use as a speech test in clinical work and research. Secondly, to assess the discrimination performance for individual tones, d' values outperform the simple proportion of correct responses.

Reference sound pressure level for Korean speech audiometry.

OBJECTIVE: The purpose of this study was to examine the reference sound pressure level (RSPL) for Korean speech audiometry which was defined as the reference speech recognition threshold level (RSRTL) equivalent to 0 dB HL at the audiometer. STUDY SAMPLE: Subjects consisted of 20 adults (40 ears) with normal hearing sensitivity. DESIGN: Puretone thresholds (PTs) were obtained in 2 dB steps at each octave band. The newly developed Korean bisyllabic words were used to establish the speech recognition thresholds (SRTs). The SRT was the level at 50% correct responses based on the psychometric function performed from -8 dB HL (12 dB SPL) up to the level at or above 90% correct responses in 2 dB steps. RESULTS CONCLUSIONS: The mean SRT was 23.44 dB SPL for sets comprised of 36 Korean bisyllabic words. Thus, the difference between English and Korean RSRTLs was about 3.44 dB. We recommend further study to recalculate the RSRTL for Korean speech audiometry with more subjects.

The development of psychometrically equivalent Cantonese speech audiometry materials.

OBJECTIVE: The aim of this study was to develop and psychometrically evaluate speech audiometry materials that can be used to measure word recognition (WR) and speech recognition testing (SRT) in quiet for native speakers of Cantonese. STUDY SAMPLE: Commonly used bisyllabic and trisyllabic Cantonese words were digitally recorded by native male and female talkers and then evaluated by twenty normal-hearing Cantonese listeners. DESIGN: The recorded bisyllabic words were psychometrically evaluated and arranged into four WR lists and eight half-lists that are relatively homogeneous in audibility. Using logistic regression, SRT materials were developed by selecting 28 trisyllabic words with relatively steep psychometric functions and digitally adjusting their intensity to match the listeners' mean pure-tone average. RESULT: The mean psychometric slopes for the WR materials were 7.5%/dB for the male talker and 7.6%/dB for the female talker, with no statistically significant differences between the lists or half-lists. At intensity levels required for 50% intelligibility, the mean psychometric slopes of the male and female talker SRT materials were 14.5%/dB and 14.9 %/dB, respectively. CONCLUSION: High-quality digital recordings of Cantonese speech audiometric WR and SRT materials were developed and validated in this study. These materials are available on compact disc, indexed by talker gender.

The North American Listening in Spatialized Noise-Sentences test (NA LiSN-S): normative data and test-retest reliability studies for adolescents and young adults.

BACKGROUND: The Listening in Spatialized Noise-Sentences test (LiSN-S; Cameron and Dillon, 2009) was originally developed to assess auditory stream segregation skills in children aged 6 to 11 yr with suspected central auditory processing disorder. The LiSN-S creates a three-dimensional auditory environment under headphones. A simple repetition-response protocol is used to assess a listener's speech reception threshold (SRT) for target sentences presented in competing speech maskers. Performance is measured as the improvement in SRT in dB gained when either pitch, spatial, or both pitch and spatial cues are incorporated in the maskers. A North American-accented version of the LiSN-S (NA LiSN-S) is available for use in the United States and Canada. PURPOSE: To develop normative data for adolescents and adults on the NA LiSN-S, to compare these data with those of children aged 6 to 11 yr as documented in Cameron et al (2009), and to consolidate the child, adolescent, and adult normative and retest data to allow the software to be used with a wider population. RESEARCH DESIGN: In a descriptive design, normative data and test-retest reliability data were collected. STUDY SAMPLE: One hundred and twenty normally hearing participants took part in the normative data study (67 adolescents aged 12 yr, 1 mo, to 17 yr, 10 mo, and 53 adults aged 19 yr, 10 mo, to 30 yr, 30 mo). Forty-nine participants returned between 1 and 4 mo after the initial assessment for retesting. Participants were recruited from sites in Cincinnati, Dallas, and Calgary. RESULTS: When combined with data collected from children aged 6 to 11 yr, a trend of improved performance as a function of increasing age was found across performance measures. ANOVA (analysis of variance) revealed a significant effect of age on performance. Planned contrasts revealed that there were no significant differences between adults and children aged 13 yr and older on the low-cue SRT; 14 yr and older on talker and spatial advantage; 15 yr and older on total advantage; and 16 yr and older on the high-cue SRT. Mean test-retest differences on the various NA LiSN-S performance measures for the combined child, adult, and adolescent data ranged from 0.05 to 0.5 dB. Paired comparisons revealed test-retest differences were not significant on any measure of the NA LiSN-S except low-cue SRT. Test-retest differences across measures did not differ as a function of age. Test and retest scores were significantly correlated for all NA LiSN-S measures. CONCLUSIONS: The ability to use either spatial or talker cues in isolation becomes adultlike by about 14 yr of age, whereas the ability to combine spatial and talker cues does not fully mature until closer to adulthood. By consolidating child, adolescent, and adult normative and retest data the NA LiSN-S can now been utilized to assess auditory processing skills in a wider population.

The validity of an isiZulu speech reception threshold test for use with adult isiZulu speakers.

BACKGROUND: This study continued the development of an isiZulu speech reception threshold (zSRT) test for use with first language, adult speakers of isiZulu. OBJECTIVES: The objective of this study was to determine the convergent and concurrent validity of the zSRT test. METHODS: One hundred adult isiZulu first-language speakers with normal hearing and 76 first-language, adult isiZulu speakers with conductive or sensorineural hearing losses ranging from mild to severe were assessed on pure tone audiometry and a newly developed isiZulu SRT test. Convergent validity was established through agreement of the zSRT scores with pure tone average (PTA) scores. Concurrent validity was assessed by examining the steepness of the psychometric curve for each word in the zSRT test for each type and degree of hearing loss. RESULTS: Intraclass correlation coefficient analyses showed zSRT scores were in substantial to very high agreement with PTA scores for the normal hearing and hearing loss groups (NH - right ear ICC consistency = 0.78, left ear ICC = 0.67; HL - right ear ICC consistency = 0.97, left ear ICC consistency = 0.95). The mean psychometric slope (%/dB) at 50% correct perception for all words in the zSRT test was 4.92%/dB for the mild conductive hearing loss group, 5.26%/dB for the moderate conductive hearing loss group, 2.85%/dB for the moderately severe sensorineural hearing loss group and 2.47%/dB for the severe sensorineural hearing loss group. These slopes were appropriate for the degree of hearing loss observed in each group. CONCLUSION: The zSRT test showed convergent and concurrent validity for assessing SRT in first language, adult speakers of isiZulu.

Theoretical Issues of Validity in the Measurement of Aided Speech Reception Threshold in Noise for Comparing Nonlinear Hearing Aid Systems.

BACKGROUND: Adaptive Speech Reception Threshold in noise (SRTn) measurements are often used to make comparisons between alternative hearing aid (HA) systems. Such measurements usually do not constrain the signal-to-noise ratio (SNR) at which testing takes place. Meanwhile, HA systems increasingly include nonlinear features that operate differently in different SNRs, and listeners differ in their inherent SNR requirements. PURPOSE: To show that SRTn measurements, as commonly used in comparisons of alternative HA systems, suffer from threats to their validity, to illustrate these threats with examples of potentially invalid conclusions in the research literature, and to propose ways to tackle these threats. RESEARCH DESIGN: An examination of the nature of SRTn measurements in the context of test theory, modern nonlinear HAs, and listener diversity. STUDY SAMPLE, DATA COLLECTION, AND ANALYSIS: Examples from the audiological research literature were used to estimate typical interparticipant variation in SRTn and to illustrate cases where validity may have been compromised. RESULTS AND CONCLUSIONS: There can be no doubt that SRTn measurements, when used to compare nonlinear HA systems, in principle, suffer from threats to their internal and external/ecological validity. Interactions between HA nonlinearities and SNR, and interparticipant differences in inherent SNR requirements, can act to generate misleading results. In addition, SRTn may lie at an SNR outside the range for which the HA system is designed or expected to operate in. Although the extent of invalid conclusions in the literature is difficult to evaluate, examples of studies were nevertheless identified where the risk of each form of invalidity is significant. Reliable data on ecological SNRs is becoming available, so that ecological validity can be assessed. Methodological developments that can reduce the risk of invalid conclusions include variations on the SRTn measurement procedure itself, manipulations of stimulus or scoring conditions to place SRTn in an ecologically relevant range, and design and analysis approaches that take account of interparticipant differences.

Speech Understanding in Children With Normal Hearing: Sound Field Normative Data for BabyBio, BKB-SIN, and QuickSIN.

OBJECTIVE: The primary goal was to establish normative data for the Pediatric AzBio "BabyBio," QuickSIN, and BKB-SIN measures in the sound field for children with normal hearing. SETTING: Tertiary care hospital; cochlear implant (CI) program. PATIENTS: Forty-one children with normal hearing were recruited across four age groups (5-6, 7-8, 9-10, and 11-12 yr). INTERVENTIONS: Sentence recognition testing was assessed at four different signal-to-noise ratios (SNRs, +10, +5, 0, and -5 dB) for BabyBio sentences as well as for the BKB-SIN and QuickSIN tests. All measures were presented in the sound field at 60 dBA except QuickSIN, which was presented at 70 dBA. MAIN OUTCOME MEASURES: BabyBio sentence recognition, BKB-SIN SNR-50, and QuickSIN SNR-50 were analyzed to establish sound field norms. RESULTS: BabyBio sentence recognition approached ceiling at all SNRs with mean scores ranging from 86% at -5 dB SNR to 99.3% at +10 dB SNR. Mean QuickSIN SNR-50 was 6.6 dB. Mean BKB-SIN SNR-50 was 1.6 dB with sound field data being consistent with insert earphone normative data in the BKB-SIN manual. Performance for all measures improved with age. CONCLUSION: Children with normal hearing achieve ceiling-level performance for BabyBio sentence recognition at SNRs used for clinical CI testing (≥ 0 dB SNR) and approach ceiling level even at -5 dB SNR. Consistent with previous reports, speech recognition in noise improved with age from 5 to 12 years in children with normal hearing. Thus, speech recognition in noise might also increase in the CI population across the same age range warranting age-specific norms for CI recipients. Last, the QuickSIN test could be substituted for the BKB-SIN test with appropriate age-normative data.

Mono-syllabic word test score as a pre-operative assessment criterion for cochlear implant candidature in adults with acquired hearing loss.

RATIONALE: Cochlear Implant (CI) candidates with a ski-slope hearing loss may be outside current implantation criteria [< 50% on Bamford-Kowal-Bench (BKB) sentence testing], despite having a significant hearing disability and limited benefit from conventional amplification. AIM: To use existing post-operative performance data to establish a criterion for Arthur Boothroyd (AB) word test for CI candidacy assessment. METHODOLOGY: Retrospective analysis of post-operative AB words scores for 64 CI users was performed and the 10th percentile score selected as a criterion of reasonable chance for post-operative improvement. A follow-up audit was performed 4 years later with a larger patient group of 127 CI users. OUTCOMES: An AB word score of 15% was determined using this method and became the pre-implant criterion for future patients. The same score was achieved on the follow-up audit and was adopted as an All Wales criterion as part of the National Audit process.

Preliminary assessment of the feasibility of using AB words to assess candidacy in adults.

BACKGROUND: Adult cochlear implant (CI) candidacy is assessed in part by the use of speech perception measures. In the United Kingdom the current cut-off point to fall within the CI candidacy range is a score of less than 50% on the BKB sentences presented in quiet (presented at 70 dBSPL). GOAL: The specific goal of this article was to review the benefit of adding the AB word test to the assessment test battery for candidacy. RESULTS: The AB word test scores showed good sensitivity and specificity when calculated based on both word and phoneme scores. The word score equivalent for 50% correct on the BKB sentences was 18.5% and it was 34.5% when the phoneme score was calculated; these scores are in line with those used in centres in Wales (15% AB word score). CONCLUSION: The goal of the British Cochlear Implant Group (BCIG) service evaluation was to determine if the pre-implant assessment measures are appropriate and set at the correct level for determining candidacy, the future analyses will determine whether the speech perception cut-off point for candidacy should be adjusted and whether other more challenging measures should be used in the candidacy evaluation.

Hearing in Noise Test Brazil: standardization for young adults with normal hearing.

INTRODUCTION: Individuals with the same ability of speech recognition in quiet can have extremely different results in noisy environments. OBJECTIVE: To standardize speech perception in adults with normal hearing in the free field using the Brazilian Hearing in Noise Test. METHODS: Contemporary, cross-sectional cohort study. 79 adults with normal hearing and without cognitive impairment participated in the study. Lists of Hearing in Noise Test sentences were randomly in quiet, noise front, noise right, and noise left. RESULTS: There were no significant differences between right and left ears at all frequencies tested (paired t-1 test). Nor were significant differences observed when comparing gender and interaction between these conditions. A difference was observed among the free field positions tested, except in the situations of noise right and noise left. CONCLUSION: Results of speech perception in adults with normal hearing in the free field during different listening situations in noise indicated poorer performance during the condition with noise and speech in front, i.e., 0°/0°. The values found in the standardization of the Hearing in Noise Test free field can be used as a reference in the development of protocols for tests of speech perception in noise, and for monitoring individuals with hearing impairment.