Psychometrically equivalent bisyllabic words for speech recognition threshold testing in Vietnamese.

OBJECTIVE: This study identified, digitally recorded, edited and evaluated 89 bisyllabic Vietnamese words with the goal of identifying homogeneous words that could be used to measure the speech recognition threshold (SRT) in native talkers of Vietnamese. DESIGN: Native male and female talker productions of 89 Vietnamese bisyllabic words were recorded, edited and then presented at intensities ranging from -10 to 20 dBHL. Logistic regression was used to identify the best words for measuring the SRT. Forty-eight words were selected and digitally edited to have 50% intelligibility at a level equal to the mean pure-tone average (PTA) for normally hearing participants (5.2 dBHL). STUDY SAMPLE: Twenty normally hearing native Vietnamese participants listened to and repeated bisyllabic Vietnamese words at intensities ranging from -10 to 20 dBHL. RESULTS: A total of 48 male and female talker recordings of bisyllabic words with steep psychometric functions (>9.0%/dB) were chosen for the final bisyllabic SRT list. Only words homogeneous with respect to threshold audibility with steep psychometric function slopes were chosen for the final list. CONCLUSIONS: Digital recordings of bisyllabic Vietnamese words are now available for use in measuring the SRT for patients whose native language is Vietnamese.

The effect of dialect on speech audiometry testing.

PURPOSE: In this study, the authors examined the validity of using materials from 2 nonregional yet mutually intelligible dialects to evaluate an individual's speech recognition threshold (SRT) and word recognition (WR) abilities and whether a speaker of 1 dialect could accurately administer and score materials in the other dialect. METHOD: Previously created SRT and WR materials were presented to 32 Mandarin listeners with normal hearing: 16 speakers of Mainland Mandarin and 16 speakers of Taiwan Mandarin. Hearing abilities were examined using SRT and WR materials created for speakers from 2 different regional dialects. Presentation of the materials occurred during 2 test sessions, counterbalanced across material and listener dialect. Listener responses were evaluated by 2 judges; 1 spoke Mainland Mandarin, and the other spoke Taiwan Mandarin. RESULTS: For the SRT and WR results, differences in listener performance were statistically significant across material and listener dialect, with threshold differences of less than 2 dB HL when collapsed across session. The interscorer percentage of agreement was 99.5% for SRT and 99.1% for WR testing. CONCLUSION: Testing with materials in a different regional dialect does have a measurable impact on SRT and WR performance. However, this difference, though reliable, is small enough to have a negligible impact on clinical findings.

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.

Word recognition materials for native speakers of Taiwan Mandarin.

PURPOSE: To select, digitally record, evaluate, and psychometrically equate word recognition materials that can be used to measure the speech perception abilities of native speakers of Taiwan Mandarin in quiet. METHOD: Frequently used bisyllabic words produced by male and female talkers of Taiwan Mandarin were digitally recorded and subsequently evaluated using 20 native listeners with normal hearing at 10 intensity levels (-5 to 40 dB HL) in increments of 5 dB. RESULTS: Using logistic regression, 200 words with the steepest psychometric slopes were divided into 4 lists and 8 half-lists that were relatively equivalent in psychometric function slope. To increase auditory homogeneity of the lists, the intensity of words in each 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. CONCLUSIONS: Digital recordings of the word recognition lists and the associated clinical instructions are available on CD upon request.

Development of speech reception threshold materials for speakers of Taiwan Mandarin.

The aim of this research was to develop, digitally record, evaluate, and equate speech audiometry materials that can be used to measure the speech reception threshold (SRT) in quiet for native speakers of Taiwan Mandarin. Familiar trisyllabic words were digitally recorded by male and female talkers of Taiwan Mandarin and subsequently evaluated by 20 native listeners with normal hearing at 14 intensity levels (-10 to 16 dB HL) in 2 dB increments. Using logistic regression, psychometric functions were calculated for all words. Twenty-eight words with comparatively steep psychometric functions were selected and digitally adjusted to match the mean subject pure-tone average (5.0 dB HL). This resulted in a list of words that are relatively homogeneous in threshold audibility and psychometric function slope. The mean slopes for the 28 selected male and female trisyllabic Taiwan Mandarin words were 11.3%/dB and 11.7%/dB, respectively.

Psychometrically equivalent Russian speech audiometry materials by male and female talkers.

Despite the large number of individuals who speak Russian, only a limited number of high-quality speech audiometry materials are available in a standard dialect of Russian. Thus, the purpose of this study was to develop and evaluate speech audiometry materials that can be used to measure word recognition and SRT testing in quiet for native speakers of Russian. Familiar monosyllabic and bisyllabic words were digitally recorded by male and female talkers of Russian and subsequently evaluated by native listeners. Using logistic regression, psychometric functions were then calculated for all words. Selected monosyllabic words were digitally adjusted to create word recognition lists which are relatively homogeneous with respect to audibility and psychometric slope. Speech reception threshold materials were developed by selecting twenty-five bisyllabic words with relatively steep psychometric function slopes (12.1%/dB and 9.9 %/dB) and digitally equating their intensity to match the mean PTA of the native listeners. Digital recordings of the resulting psychometrically equivalent speech audiometry materials are available on compact disc.

Psychometrically equivalent Mandarin bisyllabic speech discrimination materials spoken by male and female talkers.

The purpose of this study was to develop, digitally record, evaluate, and psychometrically equate a set of Mandarin bisyllabic word lists for use in measurement of speech discrimination. Familiar bisyllabic words were digitally recorded by male and female talkers of Standard Mandarin. Percentage of correct word recognition was measured for each word at ten intensity levels ( -5 to 40 dB HL) in 5 dB increments using 20 normally hearing subjects. Using logistic regression, 200 words with the steepest logistic regression slopes were included in four psychometrically equivalent word lists of 50 words each, and eight half-lists of 25 words each. To increase auditory homogeneity of the lists, the intensity of words in each 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. Digital recordings of the psychometrically equivalent word recognition lists are available on compact disc.

Psychometrically equivalent trisyllabic words for speech reception threshold testing in Mandarin.

The aim of this investigation was to develop, digitally record, evaluate, and equate Mandarin trisyllabic words, which could then be used to measure the SRT. A selection of 90 frequently utilized trisyllabic words were digitally recorded by male and female talkers of Standard Mandarin and presented to 20 normally hearing subjects at 13 intensity levels (-10 to 14dB HL) in 2dB increments. Using logistic regression, psychometric functions were then calculated for all words. Twenty-four trisyllabic words with steep psychometric function slopes were selected, and their intensities were digitally adjusted to match the mean subject PTA (3.0 dB HL). The mean slopes for the 24 selected male and female trisyllabic Mandarin Chinese words were 11.3%/dB and 12.1%/dB, respectively. Thus we developed a list of words which were homogeneous with respect to audibility and slope. Digital recordings of the psychometrically equivalent trisyllabic words are available on compact disc.

West Nile virus infection among health-fair participants, Wyoming 2003: assessment of symptoms and risk factors.

Wyoming experienced heavy West Nile virus (WNV) activity for the first time in 2003 and the area hardest hit was Goshen County. Little was known about the epidemiology of WNV in this region. This study describes the symptomatology of WNV and the association between certain behaviors and infection in Goshen County. Study participants were recruited from attendees of a health-fair sponsored by a local hospital, held October 1-3, 2003. A blood sample for WNV testing was obtained from each participant, and participants completed a questionnaire seeking information about the presence of specified symptoms consistent with WNV infection and risk factors possibly associated with infection. The samples were tested for anti-WNV IgM and IgG at the Wyoming Public Health Laboratory. Eight-hundred sixty-nine residents of Goshen County participated, and 122 (14.0%) were seropositive for anti-WNV IgM or IgG. Sixty (59.4%) of 101 persons seropositive for anti-WNV IgM experienced at least one symptom in the previous 4 months consistent with WNV infection, compared with 323 (43.2%) of 747 seronegative persons, resulting in an attributable risk of WNV seropositivity of 16.2%. Of the many symptoms queried, muscle aches (OR 2.63, 95% CI 1.69-4.09), skin rash (OR 6.35, 95% CI 3.74-10.80), fever (OR 2.56, 95% Cl 1.50-4.36), and muscle weakness (OR 2.33, 95% CI 1.34-4.02) were significantly associated with seropositivity on univariate analysis. By multivariate analysis, only skin rash remained significant. Risk factor analysis showed those spending > or =3 hours outside per day were more likely to be seropositive than those spending less time outside per day ( p < 0.05). This study corroborates the belief that a minority of persons infected with WNV develop symptoms attributable to WNV, and also demonstrates that some symptoms are more significantly associated with infection than others.

A Simplified Method for Calibrating a Sound-Level Meter for Use With a Brüel & Kjær Artificial Mastoid.

The standard method for calibrating a sound-level meter for use with the Brüel & Kjær Artificial Mastoid for bone vibrator tests entails the use of a signal generator, a precision voltmeter, and possibly a frequency counter. This equipment should be certified annually and traceable to the National Institute of Standards and Technology (NIST), and its use generally restricts calibration to a laboratory environment and requires a considerable amount of time. We have developed a simplified method for calibrating the sound-level meter by using a sound-level calibrator and microphone. Using the known sensitivities of the microphone and the artificial mastoid, the sound-level calibrator used for calibration of the microphone may also be used for calibration of the sound-level meter to measure force levels with the artificial mastoid.