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 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.