Speech reception threshold (SRT) tools have been developed to assist in the evaluation of hearing. This study was performed to develop, digitally record, evaluate, and equate Taiwan Mandarin trisyllabic words which can be used to measure the SRT. Eighty-nine commonly used trisyllabic words were chosen and digitally recorded by native male and female speakers. The words were then presented to 20 normally hearing subjects at 14 intensity levels (-10 to 16 dB HL) with 2 dB increments. Psychometric function slopes were calculated using logistic regression. Twenty-eight words with steep psychometric function were selected and digitally adjusted to match the mean subject pure-tone average (5.0 dB HL). A list of 28 trisyllabic words which were relatively homogeneous in audibility and slope were developed. The mean slopes for the 28 selected male and female trisyllabic Taiwan Madarin words were 11.3 %/dB (male talker) and 11.7 %/dB (female talker), respectively. Digital recordings of the psychometrically equivalent trisyllabic words are available on compact disc.

Digits-in-noise (DIN) tests have become very popular over the past 15 years for hearing loss detection. Several recent studies have highlighted the potential utility of digits-in-noise (DIN) as a school-aged hearing test. However, age may influence test performance in children. In addition, a new antiphasic stimulus paradigm has been introduced. This study determined the maturation of speech recognition for diotic and antiphasic DIN in children and evaluated DIN self-testing in young children. A cross-sectional, quantitative, quasi-experimental research design was used in this study. Participants with confirmed normal hearing were tested with diotic and antiphasic DIN test. During the DIN test, arrangements of three spoken digits were presented in noise via headphones at varying signal-to-noise ratios (SNRs). The researcher entered each three-digit sequence the participant said on a smartphone keypad. Six hundred and twenty-one normal hearing (bilateral pure tone threshold of ≤ 20 dB HL at 1, 2, and 4kHz) children between the ages of 6-13 years with normal hearing were recruited in order to examine the comparative maturation of diotic and antiphasic performance. A further sample of 30 first grade (7-year-old) children with normal hearing were recruited to determine the validity of self-testing on a smartphone. Multiple regression analysis including age, gender, and English additional language (i.e. Person whose first language or home language is not English) showed only age to be a significant predictor for both diotic and antiphasic SRT (p < 0.05). Speech reception thresholds improved by 0.15 dB and 0.35 dB SNR per year for diotic and antiphasic SRT, respectively. Post hoc multiple age group comparisons using Bonferroni adjustment for multiple comparisons (by year) showed SRTs for young children (6 to 9 years old) differed significantly from older children (11 to 13 years old) (p < 0.05). There was no significant difference in SRT between age 10 and upward. Self- and facilitated testing in young children was significantly (p > 0.05) different for the antiphasic condition and demonstrated poor reliability in diotic and antiphasic conditions. Increasing age was significantly associated with improved SRT using diotic and antiphasic DIN. Beyond 10 years of age, SRT results of children became more adult-like. However, age effects were only significant up to 10 and 12 years for antiphasic and diotic SRT, respectively. Furthermore, between self- and facilitated testing, the SRT difference was not significant (p > 0.05). / Dissertation (MA)--University of Pretoria, 2019. / Speech-Language Pathology and Audiology / MA / Unrestricted

The use of speech audiometry is essential in audiological testing. One of the most important elements of speech audiometry is speech reception threshold. To provide services for the growing population of non-English speaking people, audiologists need speech audiometry materials in a variety of languages. The purpose of this study was to develop, digitally record, evaluate, and equate Arabic bisyllabic words for use in testing speech reception threshold. Ninety frequently used bisyllabic words were digitally recorded by a male talker of standard Arabic. These words were presented to 20 normally hearing subjects in 2 dB increments at intensity levels ranging from -10 to 22 dB HL. Psychometric functions were then determined for all 90 words using logistic regression. Words with steep psychometric functions were selected for inclusion in the test CD. The intensities of these selected words were adjusted to match the mean subject PTA within 2 dB, and a list of words was developed which was homogenous with respect to slope and audibility. The words are contained on tracks 2 and 3 of the Brigham Young University Arabic Speech Audiometry Materials (Disc 1.0) CD.

The purpose of this study was to develop, digitally record, evaluate, and equate Mongolian monosyllabic and bisyllabic child-appropriate words which can be used in the measurement of word recognition scores and speech-reception threshold (SRT) in children who are native speakers of Mongolian. Based on data collected from a survey of Mongolian child language professionals, a subset of child-appropriate materials was adapted from a set of materials developed for Mongolian adults. Two lists of 50 monosyllabic words and four half-lists of 25 words each were developed for testing the word recognition abilities of Mongolian children. The developed lists and half-lists were found to be statistically equivalent in terms of audibility and psychometric slope, with average psychometric function slopes (at 50% intelligibility) of 6.41 %/dB for the male recordings and 5.84 %/dB for the female recordings. Given the structure and limitations of the study, a valid set of child-appropriate SRT materials could not be developed. It is likely that the inability to obtain a subset of SRT words was due in part to large differences between the mean PTA of the subjects and the threshold for 50% intelligibility, as well as the inability to represent most of the selected words pictographically. However the information gained from this study provides additional insight that may aid the future development of child-appropriate Mongolian SRT materials. Digital recordings of the resulting psychometrically equivalent child- appropriate speech audiometry materials are available on compact disc.

The purpose of this study was to develop digitally recorded speech audiometry materials in the Japanese language to evaluate Speech Reception Threshold (SRT) and speech discrimination. Trisyllabic words were used to evaluate the SRT and bisyllabic words were used for speech discrimination. Words were recorded by one native female talker and one native male talker who were judged as having standard Japanese dialects. Twenty native Japanese speakers between the ages of 20 and 32 were used as subjects to evaluate 69 trisyllabic words across 13 different intensity levels. The 25 trisyllabic words with the steepest psychometric function (%/dB) were selected for inclusion in the final CD. The final trisyllabic words were digitally adjusted so that the threshold of each word was equal to the mean PTA (3.42 dB HL) of all the subjects. The mean psychometric function (%/dB) at 50% for the trisyllabic words was 9.6 %/dB for the male talker and 7.7 %/dB for the female talker. The same 20 subjects were also used to evaluate 240 bisyllabic words across 10 different intensity levels. A logistic regression was used to obtain regression slopes for each of the 240 words. The 200 bisyllabic words with the steepest slope were selected for inclusion in the final CD. Four lists of 50 words each and eight half-lists of 25 words each were created from the selected bisyllabic words. A chi-square statistic revealed no significant differences among the lists or half-lists. The mean psychometric function at 50% for the bisyllabic lists and half-lists was 5.9 %/dB for the male talker and 5.2 %/dB for the female talker.

The development of digitally recorded speech audiometry materials in Mandarin Chinese has been limited to date. High quality materials proliferate in the English language and have been developed for other languages such as Brazilian Portuguese, Spanish, Japanese, Korean, French, Italian, Polish, and Russian. The aims of this study were to develop, digitally record, evaluate, and equate words and word lists in Mandarin Chinese to use for speech reception threshold testing and for speech discrimination testing. The words that were evaluated were chosen from a Chinese frequency usage dictionary. One native male and one native female talker recorded the words onto a compact disc. These words were then evaluated on 20 normally-hearing subjects, all of whom were natives of mainland China. Following the tests, the words and word lists were analyzed using logistic regression. For speech reception threshold testing, 24 Mandarin Chinese trisyllabic words with steep psychometric function slopes were selected. Their intensities were adjusted to match the mean subject pure-tone average of 3.0 dB HL. The mean slopes for these selected male and female trisyllabic words were 11.3 %/dB and 12.1 %/dB, respectively. For the speech discrimination testing, the 200 bisyllabic words with the steepest logistic regression slopes were divided among four psychometrically equivalent lists of 50 words each and eight half-lists of 25 words each. The intensity of each word list was digitally adjusted so that the threshold of each list was equal to the midpoint between the mean thresholds of the male and female half-lists. All lists were homogeneous with respect to audibility and psychometric function slope. Digital recordings of the psychometrically equivalent word lists are included on a compact disc.

The purpose of this study was to create psychometrically equivalent word lists in the language of Cantonese for word recognition testing. Frequently used bisyllabic Cantonese words were recorded by a native female and male talker. The word lists were evaluated by administering the word recognition lists to 20 native speakers of Cantonese with normal hearing. Each list was presented at 10 different intensity levels ranging from -5 to 40 dB HL in 5 dB increments. Logistic regression was used to determine the words with the steepest logistic regression slopes. The 200 words with the steepest slopes were then formulated into four lists of 50 words and eight half-lists of 25 words. The mean psychometric slope value at the 50% location for the male talker was 7.5%/dB while the mean slope for the female talker was slightly steeper at 7.6%/dB. The word lists were digitally recorded on compact discs for worldwide use.

In addition to the use of pure-tones for testing hearing, speech signals are highly valuable diagnostic tools for identifying and evaluating hearing impairment. Speech audiometry involves the implementation of such signals in the measurement of hearing acuity. One aspect of speech audiometry involves assessment of the speech recognition threshold (SRT) which evaluates an individual's ability to hear and understand speech. While live speech has been used in the past to assess SRT, recorded materials are preferred and have been shown to be advantageous over live speech. High-quality digitally recorded speech audiometry materials have been available in English for some time, but assessment of individuals using speech materials from a language that they do not speak natively has been shown to be both inadequate and inaccurate. Speech audiometry materials have recently become available in many languages. Currently, however, there are no known published recordings for assessment of SRT in the Tagalog language. The goal of this study was to develop psychometrically equivalent speech audiometry materials for measuring speech recognition threshold in Tagalog. During this study Tagalog words were initially recorded by a native speaker selected for accent and vocal quality. The words were reduced down to 90 words to be evaluated in the study. Each of the 90 trisyllabic words were evaluated at 2 dB increments from -10 to 16 dB HL by 20 native Tagalog speakers, all having normal hearing. Based on the results, 34 trisyllabic Tagalog words were selected based on their familiarity to native listeners, relative homogeneity with regards to audibility and psychometric function slope. Each word was then adjusted to make the 50% performance threshold equal to the mean PTA of the 20 research participants (4.3 dB HL). The final edited words were then digitally recorded onto compact disc for distribution and for use in assessing SRT in native Tagalog speakers worldwide.

The purpose of this study was to develop, digitally record, evaluate, and equate Cantonese trisyllabic words which could then be used in the measurement of the speech reception threshold. A selection of 90 frequently utilized trisyllabic words were selected and then digitally recorded by male and female talkers of Standard Cantonese and presented to 20 subjects with normal hearing beginning at 6 dB below their pure-tone average (PTA) and ascending in 2 dB increments until one of the following criteria had been met: (a) the participant responded correctly to 100% of the test items, or (b) the presentation level reached 16 dB HL. Using logistic regression, psychometric functions were calculated for each word. Twenty-eight trisyllabic words with the steepest psychometric function slopes were selected. The psychometric function slopes for the 28 selected words, at 50% threshold, ranged from 10.3 %/dB to 19.6 %/dB (M = 14.5 %/dB) for the male talker and from 10.3 %/dB to 22.7 %/dB (M = 14.9 %/dB) for the female talker. To decrease the variability among the words the intensities were digitally adjusted to match the mean subject PTA (4.5 dB HL). The resulting lists included mean slopes from 20 to 80% with of a range of 8.9 %/dB to 16.9 %/dB (M = 12.6 %/dB) for the male talker and a range of 8.9 %/dB to 19.7 %/dB (M = 12.9 %/dB) for the female talker. Digital recordings of the psychometrically equivalent trisyllabic words are available on compact disc.