Lena L. N. Wong

Development of the Mandarin Hearing In Noise Test (MHINT)

Objective: To develop two versions of the Mandarin Hearing In Noise Test (MHINT). These tests are adaptive tests that measure the reception threshold for sentences (RTSs) in quiet and in noise. The RTS is the presentation level at which half the sentences are correctly recognized. Design: Four studies were undertaken to (1) develop sentence materials, (2) equalize sentence difficulty, (3) create phonemically balanced sentence lists; and (4) evaluate within-list response variability, inter-list reliability, and produce normative data. A total of 137 native Mandarin (Putonghua) speaking subjects in Mainland China and 89 native Mandarin speakers in Taiwan participated. They had normal hearing thresholds at 25 dB HL or better. RTSs were measured under four headphone test conditions: Quiet, and in noise with noise originating from the 0 degree (Noise Front), 90 degrees to the right (Noise Right), and 90 degrees to the left (Noise Left). The speech originated from the front (0 degree) in all conditions. The noise level was fixed at 65 dBA, and the speech was varied adaptively to find the RTS. Results: Two versions of the test materials, consisting of 24, 20-sentence lists each in Mandarin spoken in the Mainland (the MHINT-M) and the dialect of Mandarin spoken in Taiwan (the MHINT-T), were created from two sets of 240 sentences containing 10 syllables per sentence. The mean Quiet RTS was 14.7 dBA, using the MHINT-M, and 19.4 dBA, using the MHINT-T. Using the MHINT-M, the mean RTS for Noise Front was –4.3 dB signal-to-noise ratio (SNR), –11.7 dB SNR for Noise Right, and –11.7 dB SNR for Noise Left. Using the MHINT-T, the Noise Front RTS was –4.0 dB SNR, –10.7 dB SNR for Noise Right, and –11.0 dB SNR for Noise Left. Results in noise are slightly better than those seen for the English HINT norms. Response variability within list was low, and inter-list reliability was high, indicating that consistent results can be obtained using any list. Confidence intervals are reported. Conclusions: The two versions of the MHINT are the first standardized Mandarin sentence speech intelligibility tests. Similar to other language versions of the HINT, the MHINT was developed using the same rationale as the English HINT, allowing norm-referenced results for the MHINT to be compared directly with results in other languages. The MHINT would benefit from further evaluation of its validity.

Assessment of speech intelligibility in noise with the Hearing in Noise Test

Assessment of speech intelligibility in noise in clinical settings, as well as in the laboratory, presents a wide variety of challenges. Developers of the hearing in noise test (HINT) have attempted to address these challenges through application of a number of methodological assumptions and procedures, and by constraining the type of speech materials used in the test. These assumptions and constraints have allowed the HINT to be developed in a number of several different languages and to provide comparable measures of speech intelligibility in noise for each language. This introductory paper discusses the challenges of assessing speech intelligibility in noise, the approach used with the HINT, and the implications of the assumptions and constraints when interpreting test results. Difficulty in measuring speech intelligibility in noise occurs, in large part, because of the many factors that influence intelligibility in noise. Each of these factors introduces a source of variability that can affect the measure. In the following paragraphs, we discuss each factor and describe the approach that has been used to address these factors in the development of the HINT. Our approach is motivated by the primary purpose for administering the HINT*to assess the effects of an individual’s hearing on their speech intelligibility in noise. These effects are assessed in two different ways with the HINT. One is a withinsubject, or relative, comparison of an individual’s speech intelligibility between two or more conditions (e.g. when using hearing aid A or hearing aid B). The other is a between-subjects comparison of an individual’s speech intelligibility as it relates to that of the average normal hearing individual. This comparison places the individual on a scale of speech intelligibility defined by the norms that accompany the HINT in each language.

Development of the Cantonese Hearing In Noise Test (CHINT)

Objective: To develop a Cantonese version of the Hearing In Noise Test (CHINT) with the same features as the English Hearing In Noise Test (HINT) (Nilsson, Soli, & Sullivan, 1994). Design: The CHINT was developed in five separate studies: (1) evaluation of initial materials; (2) creation of sentence materials; (3) equalization of sentence difficulty; (4) creation of sentence lists; and (5) evaluation of response variability, inter-list reliability, and establishment of norms. Using the CHINT material, reception thresholds for sentences were measured under four headphone test conditions: Quiet, and in noise with noise simulated as originating from 0° (noise front), 90° (noise right), and 270° (noise left). The speech source was located at 0° in all conditions. The locations of the speech and noise sources were simulated using virtual audio processing, as with the English HINT. The noise conditions consisted of listening with noise fixed at 65 dBA with the level of speech varied in an adaptive procedure. A total of 142 subjects with normal hearing thresholds participated in the five studies. Results: Two versions of the test materials, twenty-four 10-sentence lists and twelve 20-sentence lists, were created from a single set of 240 sentences containing 10 syllables per sentence. Using the twenty-four 10-sentence lists, mean thresholds under earphones in quiet were measured at 19.4 dBA and reception thresholds for sentences of −3.9 dB for noise front, −10.6 dB for noise right, and −10.5 dB for noise left. Similar results were obtained using the 20-sentence lists (19.4, −4.0, −10.9, and −11.0 dB, respectively, for quiet, noise front, noise right, and noise left conditions). There was low response variability within each list. High inter-list reliability suggests that consistent results could be obtained using any list. Confidence intervals are reported. The CHINT norms for listening in quiet and noise conditions were comparable to those for the English HINT. Conclusions: The CHINT is the first standardized Cantonese sentence speech intelligibility test. The CHINT was developed using the same rationale as the English HINT, allowing norm reference results from the two tests to be compared directly across languages. Results showed the CHINT is a reliable test. The CHINT would benefit from further evaluation of validity.

Hearing Aid Satisfaction: What Does Research from the Past 20 Years Say?

Hearing aid satisfaction is a pleasurable emotional experience as an outcome of an evaluation of performance. Many tools have been designed to measure the degree of satisfaction overall, or along the dimensions of cost, appearance, acoustic benefit, comfort, and service. Various studies have used these tools to examine the relationships between satisfaction and other factors. Findings are not always consistent across studies, but in general, hearing aid satisfaction has been found to be related to experience, expectation, personality and attitude, usage, type of hearing aids, sound quality, listening situations, and problems in hearing aid use. Inconsistent findings across studies and difficulties in evaluating the underlying relationships are probably caused by problems with the tools (eg, lack of validity) and the methods used to evaluate relationships (eg, correlation analyses evaluate association and not causal effect). Whether satisfaction changes over time and how service satisfaction contributes to device satisfaction are unclear. It is hoped that this review will help readers understand current satisfaction measures, how various factors affect satisfaction, and how the way satisfaction is measured may be improved to yield more reliable and valid data.

Assessing the perceptual contributions of vowels and consonants to Mandarin sentence intelligibility

This study investigated the perceptual contributions of vowels and consonants to Mandarin sentence intelligibility. Mandarin sentences were edited using a noise-replacement paradigm to preserve various amounts of segmental information and presented to normal-hearing listeners to recognize. The vowel-only Mandarin sentences yielded a remarkable 3:1 intelligibility advantage over the consonant-only sentences. This advantage is larger than that obtained with English sentences, suggesting that vowels may have a greater contribution to sentence intelligibility in Mandarin than in English. Although providing information redundant to contributions from vowel centers, a little vowel-consonant boundary transition would significantly improve the intelligibility of the consonant-only Mandarin sentences.

Development of the Cantonese speech intelligibility index

A Speech Intelligibility Index (SII) for the sentences in the Cantonese version of the Hearing In Noise Test (CHINT) was derived using conventional procedures described previously in studies such as Studebaker and Sherbecoe [J. Speech Hear. Res. 34, 427-438 (1991)]. Two studies were conducted to determine the signal-to-noise ratios and high- and low-pass filtering conditions that should be used and to measure speech intelligibility in these conditions. Normal hearing subjects listened to the sentences presented in speech-spectrum shaped noise. Compared to other English speech assessment materials such as the English Hearing In Noise Test [Nilsson et al., J. Acoust. Soc. Am. 95, 1085-1099 (1994)], the frequency importance function of the CHINT suggests that low-frequency information is more important for Cantonese speech understanding. The difference in ,frequency importance weight in Chinese, compared to English, was attributed to the redundancy of test material, tonal nature of the Cantonese language, or a combination of these factors.

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.

Tone and sentence perception in young Mandarin-speaking children with cochlear implants

OBJECTIVESnThe purpose of this study was to examine the outcomes of cochlear implantation in young children in terms of (1) perception of lexical tones in quiet, (2) perception of sentences in quiet and in noise, (3) the effects of five demographic variables (i.e., preoperative hearing level, age at implantation, duration of cochlear implants use, maternal educational level, and whether a child underwent a hearing aid trial before implantation) on lexical tone perception and sentence perception, and (4) the relationship between lexical tone perception and sentence perception.nnnMETHODSn96 participants, aged from 2.41 years to 7.09 years, were recruited in mainland China. The children exhibited normal cognitive abilities and received unilateral implants at an average age of 2.72 years, with ages ranging from 0.69 to 5 years of age.nnnRESULTSnThe mean score for tone identification was 77% (SD=13%; chance level=50%). Tone 2/tone 3 was the most difficult tone contrast to identify. Children with a longer duration of CI use and whose mothers had more years of education tended to perform better in sentence perception in quiet and in noise. Having undergone a hearing aid trial before implantation and more residual hearing were additional factors contributing to better sentence perception in noise. The only demographical variable that related to tone perception in quiet was duration of CI. In addition, while there was a modest correlation between tone perception and sentence perception in quiet (rs=0.47, p<0.001), the correlation between tone perception in quiet and sentence perception in noise was much weaker (rs=-0.28, p<0.05).nnnCONCLUSIONSnThe findings suggested that most young children who had been implanted before 5 years of age and had 1-3 years of implant use did not catch up with their aged peers with normal hearing in tone perception and sentence perception. The weak to moderate correlation between tone perception in quiet and sentence perception might imply that the improvement of tone perception in quiet may not necessarily contribute to sentence perception, especially in noise condition.

Satisfaction with hearing aids: A consumer research perspective

This research aimed at describing satisfaction with hearing aids from the perspective of the client as a consumer. A disconfirmation-expectancy model, derived from consumer research, was evaluated. This model posits that pre-fitting expectations, post-fitting performance, and the experience of how performance compares to expectations (disconfirmation), contribute to satisfaction. Positive disconfirmation occurs when performance is better than original expectations and is associated with higher satisfaction. Negative disconfirmation is when performance is poorer than expectations and is associated with dissatisfaction. New hearing aid users in Hong Kong (N=42) were tested with a newly developed self-report measure (PHACS: profile of hearing aid consumer satisfaction) that included items focused on hearing ability, problems, cost, and service. Pre-fitting expectations and post-fitting performance, disconfirmation, and satisfaction were measured. Results showed that expectations were generally not related to satisfaction, that disconfirmation was correlated with many aspects of satisfaction, and that performance was most strongly related to satisfaction. The implications of the findings are that hearing aid performance is the most important element for determining satisfaction; however disconfirmation should not be overlooked.

The Mainland Mandarin Hearing in Noise Test

Preparation of test materials A pediatric audiologist constructed 830 sentences that consist of 10 characters, using words made up of one to three characters. The length of these sentences was found appropriate to use in tonal language testing (Wong & Soli, 2005). Written sentences were rated for naturalness by 10 native Mandarin speakers. Sentences with modal ratings of 5 or higher (7 being the most natural) were then read by another speaker and recorded using procedures described in Nilsson et al (1994). The recordings were rated again by five other speakers. A total of 816 sentences receiving modal ratings of 5 or higher were retained.