Outcome parameters in speech audiometry: retrospective analysis of data and reporting quality in clinical studies.

OBJECTIVES: The use of standardized outcome parameters is essential for the comparability of clinical studies. Pure-tone audiometry and speech audiometry are widely used, but there is no systematic evaluation of the outcome parameters in clinical application. Nevertheless, there is presumably a great heterogeneity especially in the field of speech audiometry. This study presents a snapshot of the current situation of documentation and usage of outcome parameters in otologic research. STUDY DESIGN: Retrospective study of existing literature analyzing common speech audiometric test material and procedure MAIN OUTCOME MEASURES: Intervention Studies from 2012 to 2016 concerning hearing ability were eligible for evaluation. Studies were analyzed with regard to study design, pathology and intervention, speech audiometric parameters, pure-tone audiometry, implementation of reporting standards and journal related data. RESULTS: 279 studies were included. Over 50% of the analyzed studies lacked proper documentation. In the remaining studies, there was a broad variance concerning the documented speech audiometric parameters, most often with a fixed presentation level of 65 dB SPL. CONCLUSION: The lack of generally used standards for reporting hearing outcomes makes it difficult to compare results of different clinical studies. An adequate description of the methods would be a first and important step in improving reports on audiological outcomes.

An Argument for Self-Report as a Reference Standard in Audiology.

BACKGROUND: The primary components of a diagnostic accuracy study are an index test, the target condition (or disorder), and a reference standard. According to the Standards for Reporting Diagnostic Accuracy statement, the reference standard should be the best method available to independently determine if the results of an index test are correct. Pure-tone thresholds have been used as the "gold standard" for the validation of some tests used in audiology. Many studies, however, have shown a lack of agreement between the audiogram and the patient's perception of hearing ability. For example, patients with normal audiograms may report difficulty understanding speech in the presence of background noise. PURPOSE: The primary purpose of this article is to present an argument for the use of self-report as a reference standard for diagnostic studies in the field of audiology. This will be in the form of a literature review on pure-tone threshold measures and self-report as reference standards. The secondary purpose is to determine the diagnostic accuracy of pure-tone threshold and Hearing-in-Noise Test (HINT) measures for the detection of a speech-recognition-in-noise disorder. RESEARCH DESIGN: Two groups of participants with normal pure-tone thresholds were evaluated. The King-Kopetzky syndrome (KKS) group was made up of participants with the self-report of speech-recognition-in-noise difficulties. The control group was made up of participants with no reports of speech-recognition-in-noise problems. The reference standard was self-report. Diagnostic accuracy of HINT and pure-tone threshold measures was determined by measuring group differences, sensitivity and specificity, and the area under the curve (AUC) for receiver-operating characteristic (ROC) curves. STUDY SAMPLE: Forty-seven participants were tested. All participants were native speakers of American English. Twenty-two participants were in the control group and 25 in the KKS group. The groups were matched for age. DATA COLLECTION AND ANALYSIS: Pure-tone threshold data were collected using the Hughson-Westlake procedure. Speech-recognition-in-noise data was collected using a software system and the standard HINT protocol. Statistical analyses were conducted using descriptive, correlational, two-sample t tests, and logistic regression. RESULTS: The literature review revealed that self-report has been used as a reference standard in investigations of patients with normal audiograms and the perception of difficulty understanding speech in the presence of background noise. Self-report may be a better indicator of hearing ability than pure-tone thresholds in some situations. The diagnostic accuracy investigation revealed statistically significant differences between control and KKS groups for HINT performance (p < 0.01), but not for pure-tone threshold measures. Better sensitivity was found for the HINT Composite score (88%) than pure-tone average (PTA; 28%). The specificities for the HINT Composite score and PTA were 77% and 95%, respectively. ROC curves revealed a greater AUC for the HINT Composite score (AUC = 0.87) than for PTA (AUC = 0.51). CONCLUSION: Self-report is a reasonable reference standard for studies on the diagnostic accuracy of speech-recognition-in-noise tests. For individuals with normal pure-tone thresholds, the HINT demonstrated a higher degree of diagnostic accuracy than pure-tone thresholds for the detection of speech-recognition-in-noise disorder.

Normative data for diagnosing auditory processing disorder in Norwegian children aged 7-12 years.

OBJECTIVE: The main purpose of this research was to obtain normative data for auditory processing tests for Norwegian speaking children. DESIGN: Participants were administered routine audiological tests and an auditory processing test-battery consisting of Filtered Words, Competing Words, Dichotic Digits, Gaps In Noise, Duration- and Frequency Pattern, Binaural Masking Level Difference and HIST Speech in Noise test. A group of 10-year-old children were retested after two weeks. The effects ear, age and gender and the test-retest reliability were investigated. STUDY SAMPLE: There were 268 normal hearing children aged 7-12 years who participated in the study. RESULTS: Results revealed no differences between genders. The children showed improving performance by age on all tests, except from the Gaps In Noise and Binaural Masking Level Difference. As expected, the children showed a right ear advantage on dichotic speech tests that decreased with age. The test-retest reliability for the tests was good, with a small learning effect on the Filtered Words test. CONCLUSION: Normative data were established and the preferred tests for diagnosing Auditory Processing Disorder were suggested for Norwegian children aged 7-12 years.

The clinical use of Arthur Boothroyd (AB) word lists in Australia: exploring evidence-based practice.

OBJECTIVE: Limited empirical investigation exists validating the use of Arthur Boothroyd (AB) word recognition materials within the Australian clinical context. The current research was undertaken to examine the evidence base and clinical implementation/interpretation of AB words in Australia. DESIGN: An on-line 22-question survey was e-mailed to members of the peak audiology professional body in Australia. STUDY SAMPLE: Three hundred and twelve responses were recorded between April and June 2015 from audiologists of a range of ages, working in various clinical settings. RESULTS: The survey results suggested audiologists use AB words on a wide range of clients from children <5 to adults ≥80 years, for diverse purposes including diagnosis of retrocochlear pathology, candidacy and validation of rehabilitative options, and client counselling. A majority of respondents reported typically administering one or two word lists per ear, and over 99% of audiologists utilised phonemic scoring. There was no consensus regarding what constitutes a significant difference between any two given scores. CONCLUSIONS: Wide variation exists in the administration and interpretation of AB words in Australia. There appears to be a mismatch between clinical utilisation of AB words and existing evidence-based empirical data. Further research is required to improve evidence-based audiologist training, and thereby current clinical use of AB words.

[Speech audiometric assessment of informational masking. German version]. / Sprachaudiometrische Erfassung von "informational masking".

BACKGROUND: In communication situations with multiple speakers, speech recognition is adversely affected by energetic masking (EM) and informational masking (IM). IM characterizes masking effects caused by irrelevant information from competing speakers. This work investigates an approach to assess IM based on the Oldenburg Sentence Test (OLSa). Furthermore, the influence of interaural time differences (ITD) and aging effects on IM are considered. MATERIALS AND METHODS: IM was measured by superimposing two sentences from the OLSa. The beginning of the target sentence was indicated by the keyword "Stefan". To segregate between target and masker sentences, ITDs from 50 to 400 µs were included. The participants were asked to selectively attend to the target sentence and repeat back the spoken words. Potential factors associated with speech recognition results were assessed by an auditory measure of temporal fine structure and a neuropsychological profile. 16 normal-hearing listeners between 18 and 77 years of age participated in the study. RESULTS: Despite the clinically normal-hearing participants, the analysis showed a significant relationship between speech recognition outcome and pure-tone thresholds. All participants benefited from small ITDs between the target and masker sentence with regard to the unmasking of IM. The magnitude of unmasking could not be explained by any of the factors assessed in this study. Error analysis and the comparison to the literature reveal that the OLSa could be a useful tool to assess IM. Also in line with the current literature is the relationship between speech recognition outcome and pure-tone thresholds, as well as the strong effect of ITDs on the release from IM. CONCLUSION: Speech audiometric assessment of IM is of high relevance with regard to everyday communication situations. Due to its structure, the OLSa seems to be a useful tool for determining IM.

[Speech audiometry for indication of conventional and implantable hearing aids]. / Sprachaudiometrie bei der Indikation von Hörhilfen und Hörimplantaten.

The social function of the human hearing apparatus is comprehension of speech. Auditory rehabilitation aims to enhance speech perception in everyday life. Consequently, audiological evaluation contains speech perception measurement. Many speech audiometric methods have been developed in German-speaking countries, which are suitable for quantification of speech perception abilities in quiet and in noise to address specific diagnostic questions. For establishment of the indication for technical hearing systems such as hearing aids and cochlear implants, the Freiburg monosyllabic test has been employed successfully for many years. Particularly sentence tests have been suggested as a complementary measure for hearing aid indication and assessment. This paper describes the characteristics and range of application of various speech audiometric methods, and highlights the methodological limitations of the individual tests.

[The systematic selection of speech audiometric procedures]. / Die systematische Auswahl von sprachaudiometrischen Verfahren.

BACKGROUND: The impact of hearing loss on the ability to participate in verbal communication can be directly quantified through the use of speech audiometry. Advances in technology and the associated reduction in background noise interference for hearing aids have allowed the reproduction of very complex acoustic environments, analogous to those in which conversations occur in daily life. These capabilities have led to the creation of numerous advanced speech audiometry measures, test procedures and environments, far beyond the presentation of isolated words in an otherwise noise-free testing booth. OBJECTIVE: The aim of this study was to develop a set of systematic criteria for the appropriate selection of speech audiometric material, which are presented in this article in relationship to the most widely used test procedures. RESULTS: Before an appropriate speech test can be selected from the numerous procedures available, the precise aims of the evaluation should be basically defined. Specific test characteristics, such as validity, objectivity, reliability and sensitivity are important for the selection of the correct test for the specific goals. CONCLUSION: A concrete understanding of the goals of the evaluation as well as of specific test criteria play a crucial role in the selection of speech audiometry testing procedures.

[Speech audiometry in expert assessment of hearing impairment]. / Sprachaudiometrie in der Begutachtung des Hörvermögens.

In the assessment process of hearing impairment the medical expert has to verify its causality and to quantify its severity as hearing loss in percentage. Based on the determined hearing loss in percentage, the degree of impairment/disability or, in the case of work-related noise-induced hearing loss, the reduction in earning capacity is estimated. In Germany the guideline for the expert assessment of work-related noise-induced hearing loss is the Königstein Guideline. Currently, the 5th edition from 2012 is used. Here, the hearing loss quantification depends mainly on the results of speech audiometry. Based on the Freiburg speech test, the hearing loss in percentage is determined using approved tables. For patients with a mild hearing loss, typically characterized by a high-frequency hearing loss, tone audiometry results are consulted additionally. Speech-in-noise tests are available and are frequently used to measure the benefit of hearing systems. They allow for the detection of these patients' hearing impairment, which generally occurs in noisy environments. The first suggestions for a table to determine hearing loss in noise in percent are available. In experimental studies it was shown that tests in quiet, other than the Freiburg speech test, can be used and the same tables can be applied. In this article the current use of speech audiometry for expert assessment is presented, and options of using further developed speech test material are discussed.

[Speech audiometry, speech perception and cognitive functions. German version]. / Sprachaudiometrie, Sprachwahrnehmung und kognitive Funktionen.

Examination of cognitive functions in the framework of speech perception has recently gained increasing scientific and clinical interest. Especially against the background of age-related hearing impairment and cognitive decline potential new perspectives in terms of better individualisation of auditory diagnosis and rehabilitation might arise. This review addresses the relationships of speech audiometry, speech perception and cognitive functions. It presents models of speech perception, discusses associations of neuropsychological with audiometric outcomes and shows recent efforts to consider cognitive functions with speech audiometry.

Evaluating recommended audiometric changes to candidacy using the speech intelligibility index.

INTRODUCTION: The National Institute of Health and Care Excellence (NICE) has derived candidacy guidelines for cochlear implants in the UK based on audiometric thresholds (90 dB HL or above at 2 and 4 kHz; hereafter referred to as the 90 dB HL criteria). Recent research has proposed that these criteria should be changed to 80 dB HL at 2 and 4 kHz (hereafter referred to as the 80 dB HL criteria) in the ear to be implanted. METHODS: In this study, we analysed aided SII scores derived for different hearing loss profiles falling within the current 90 dB HL criteria and equivalent profiles falling within the new 80 dB HL criteria. RESULTS: The aided SII scores demonstrated that the majority of potential hearing configurations falling within the new proposed 80 dB HL criteria have aided SII values of less than 0.65 (a recommended cut-off point below which there is not sufficient audibility to receive adequate benefit through hearing aids). CONCLUSIONS: This supports the proposed change to the 80 dB HL criterion level and also highlights the additional value of the SII score in supporting candidacy decisions for CI, especially for borderline candidates.

[Development and use of an APHAB database]. / Entwicklung und Anwendung einer APHAB-Datenbank.

A specific quality assurance questionnaire concerned with the provision of hearing aids was introduced that assesses elements of patient satisfaction within Germany's statutory healthcare system. A questionnaire-based assessment is now relevant for all physicians involved in the care of statutorily insured patients in Germany. The APHAB (Abbreviated Profile of Hearing Aid Benefit) questionnaire is the most widely used. The APHAB assesses several different situations: the normal hearing situation, hearing in noise, comprehension of speech in situations of echo or reverberation and hearing in loud situations. The APHAB questionnaire-based patient evaluation of the benefit of hearing aids represents the third pillar of audiological diagnostics, alongside classical pure-tone and speech audiometry. The objective of the APHAB database is to allow evaluation of individual patient data on the basis of a larger volume of data.

Intertester reliability of the acceptable noise level.

BACKGROUND: The acceptable noise level (ANL) serves to accurately predict the listener's likelihood of success with amplification. It has been proposed as a pre-hearing aid fitting protocol for hearing aid selection and counseling purposes. The ANL is a subjective measure of the listener's ability to accept background noise. Measurement of ANL relies on the tester and listener to follow the instructions set forth. To date, no research has explored the reliability of ANL as measured across clinicians or testers. PURPOSE: To examine the intertester reliability of ANL. RESEARCH DESIGN: A descriptive quasi-experimental reliability study was completed. ANL was measured for one group of listeners by three testers. STUDY SAMPLE: Three participants served as testers. Each tester was familiar with basic audiometry. Twenty-five young adults with normal hearing served as listeners. DATA COLLECTION/ANALYSIS: Each tester was stationed in a laboratory with the needed equipment. Listeners were instructed to report to these laboratories in a random order provided by the experimenters. The testers assessed most comfortable listening level (MCL) and background noise level (BNL) for all 25 listeners. RESULTS: Intraclass correlation coefficients were significant and revealed that MCL, BNL, and ANLs are reliable across testers. Additionally, one-way ANOVAs for MCL, BNL, and ANL were not significant. These findings indicate that MCL, BNL, and ANL do not differ significantly when measured by different testers. CONCLUSIONS: If the ANL instruction set is accurately followed, ANL can be reliably measured across testers, laboratories, and clinics. Intertester reliability of ANL allows for comparison across ANLs measured by different individuals. Findings of the present study indicate that tester reliability can be ruled out as a factor contributing to the disparity of mean ANLs reported in the literature.

Internationally comparable screening tests for listening in noise in several European languages: the German digit triplet test as an optimization prototype.

OBJECTIVE: A review is given of internationally comparable speech-in-noise tests for hearing screening purposes that were part of the European HearCom project. This report describes the development, optimization, and evaluation of such tests for headphone and telephone presentation, using the example of the German digit triplet test. In order to achieve the highest possible comparability, language- and speaker-dependent factors in speech intelligibility should be compensated for. MATERIALS AND METHODS: The tests comprise spoken numbers in background noise and estimate the speech reception threshold (SRT), i.e. the signal-to-noise ratio (SNR) yielding 50% speech intelligibility. RESULTS: The respective reference speech intelligibility functions for headphone and telephone presentation of the German version for 15 and 10 normal-hearing listeners are described by a SRT of -9.3 ± 0.2 and -6.5 ± 0.4 dB SNR, and slopes of 19.6 and 17.9%/dB, respectively. Reference speech intelligibility functions of all digit triplet tests optimized within the HearCom project allow for investigation of the comparability due to language specificities. CONCLUSIONS: The optimization criteria established here should be used for similar screening tests in other languages.

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.

Free-field correction values for Interacoustics DD 45 supra-aural audiometric earphones.

OBJECTIVE: This paper reports free-field correction values for the Interacoustics DD 45 audiometric earphone. The free-field correction values for earphones provide the loudness based equivalence to loudspeaker presentation. Correction values are especially used for the calibration of audiometric equipment for speech audiometry performed with headphones. Calibration values may be found in, e.g. the ISO 389 series of standards. DESIGN: The free-field correction values were determined by means of loudness balance measurements of one-third octave noises (centre frequencies 125 Hz to 8000 Hz) presented alternately from a loudspeaker in a free field and from the earphones. The procedure was essentially in accordance with the free-field frequency response procedure described in IEC 60268-7: Headphones and earphones. STUDY SAMPLE: Four earphones and 14 test subjects. RESULTS: Free field correction values are reported for the acoustic coupler IEC 60318-3 (NBS 9-A) and for the ear simulator IEC 60318-1. The results are in good agreement with the results of another independent investigation. CONCLUSIONS: The reported free-field correction values may be used as part of the basis for future standardization of the DD 45 earphone.

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.

Normative data for the Words-in-Noise Test for 6- to 12-year-old children.

PURPOSE: To establish normative data for children on the Words-in-Noise Test (WIN; R. H. Wilson, 2003; R. H. Wilson & R. McArdle, 2007). METHOD: Forty-two children in each of 7 age groups, ranging in age from 6 to 12 years (n=294), and 24 young adults (age range: 18-27 years) with normal hearing for pure tones participated. All listeners were screened at 15 dB HL (American National Standards Institute, 2004) with the octave interval between 500 and 4000 Hz. Randomizations of WIN Lists 1, 2, and 1 or WIN Lists 2, 1, and 2 were presented with the noise fixed at 70 dB SPL, followed by presentation at 90 dB SPL of the 70 Northwestern University Auditory Test No. 6 (T. W. Tillman & R. Carhart, 1966) words used in the WIN. Finally, the Peabody Picture Vocabulary Test-Revised (L. M. Dunn & L. M. Dunn, 1981) was administered. Testing was conducted in a quiet room. RESULTS: There were 3 main findings: (a) The biggest change in recognition performance occurred between the ages of 6 and 7 years; (b) from 9 to 12 years, recognition performance was stable; and (c) performance by young adults (18-27 years) was slightly better (1-2 dB) than performance by the older children. CONCLUSION: The WIN can be used with children as young as 6 years of age; however, age-specific ranges of normal recognition performance must be used.

Influence of compact disk recording protocols on reliability and comparability of speech audiometry outcomes: acoustic analysis.

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.