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Objective: A Dutch matrix sentence test was developed and evaluated. A matrix test is a speech-in-noise test based on a closed speech corpus of sentences derived from words from fixed categories. An example is "Mark gives five large flowers.", Design: This report consists of the development of the speech test and a multi-center evaluation., Study Sample: Forty-five normal-hearing participants., Results: The developed matrix test has a speech reception threshold in stationary noise of - 8.4 dB with an inter-list standard deviation of 0.2 dB. The slope of the intelligibility function is 10.2 %/dB and this is slightly lower than that of similar tests in other languages (12.6 to 17.1 %/dB)., Conclusions: The matrix test is now also available in Dutch and can be used in both Flanders and the Netherlands.

Objective: Recently, the digit triplet test was shown to be a sensitive speech-in-noise test for early high-frequency hearing loss in noise-exposed workers. This study investigates if a further improvement is achieved when using a closed set of consonant-vowel-consonant (CVC) speech items with the same vowel, and/or a low-pass (LP) filtered version of the standard speech-shaped noise., Design: Speech reception thresholds in noise were gathered for the digit triplet, CVC, and CVC_LP test and compared to the high-frequency pure-tone average (PTA)., Study Sample: 118 noise-exposed workers showing a wide range of high-frequency hearing losses., Results: For the 84 Dutch-speaking participants, the CVC test showed an increased measurement error and a decreased between-subject variation, leading to a weaker correlation with the PTA2,3,4,6 (R = 0.64) and thus a lower sensitivity compared to the digit triplet test (R = 0.86). However, the use of LP-filtered noise resulted in a sensitivity improvement (R = 0.79 versus R = 0.64) due to the large increase in between-subject spread. Similar trends were found for the 34 French-speaking workers., Conclusions: Using CVC words with the same vowel could not increase the sensitivity to detect isolated high-frequency hearing loss. With LP-filtered noise, test sensitivity improved, but it did not surpass the original digit triplet test.

Objective: To compare results on the everyday sentence test 'FIST', the new closed-set sentence test 'FrMatrix', and the digit triplet screening test 'FrDigit3'., Design: First, the FrMatrix was developed and normative values were obtained. Subsequently, speech reception thresholds (SRTs) for the three types of tests were gathered at four study centers representing different geographic regions in Belgium and France., Study Sample: Fifty-seven normal-hearing listeners took part in the normative study of the FrMatrix, and 118 subjects, with a wide range of hearing thresholds, participated in the comparative study., Results: Homogenizing the individual words of the FrMatrix with regard to their intelligibility resulted in a reference SRT of -6.0 (±0.6) dB SNR and slope at the SRT of 14.0 %/dB. The within-subject variability was only 0.4 dB. Comparison of the three tests showed high correlations between the SRTs mutually (>0.81). The FrMatrix had the highest discriminative power, both in stationary and in fluctuating noise. For all three tests, differences across the participating study centers were small and not significant., Conclusions: The FIST, the FrMatrix, and the FrDigit3 provide similar results and reliably evaluate speech recognition performance in noise both in normal-hearing and hearing-impaired listeners.

Objective: Neonatal hearing screening programs in Flanders and the Netherlands use Natus ALGO screening devices. Since 2006 in Flanders and 2009 in the Netherlands, both programs have replaced the older ALGO Portable devices with the newer ALGO 3i devices. However, in both countries, ALGO 3i devices have a significantly higher rate of referrals than ALGO Portable devices. In Flanders, the refer rate has more than doubled with the switch to ALGO 3i devices. In the Netherlands, screening centers which used ALGO 3i devices also showed a significant increase in referrals. In both countries, the percentage of children diagnosed with permanent hearing loss remained approximately the same., Design: A technical comparison of both device types was carried out to identify possible causes for the increase in referrals. The stimulus output of two ALGO Portable and three ALGO 3i devices was recorded and analysed for stimulus level, spectral properties, and stimulus irregularities., Results: ALGO 3i devices stimulate at a peak level 4.6 dB lower than ALGO Portable devices, have a different stimulus spectrum and show unexplained stimulus irregularities during 4% of the stimulation time., Conclusions: A number of technical differences were found between both device types which could explain the increase in referrals.

A French speech intelligibility screening test in noise that applies digit triplets as stimuli has been developed and evaluated for both telephone and broadband headphone use. After optimizing the speech material based on the intelligibility of the individual digits, norms for normal-hearing subjects were established. speech reception thresholds (SRTs) of -6.4 +/- 0.4 and -10.5 +/- 0.3 dB SNR, and slopes of 17.1 and 27.1 %/dB were obtained for telephone and broadband headphone presentation, respectively. The French digit triplet test by telephone was then implemented as an automatic self-screening test by home telephone, and further evaluated in normal-hearing and hearing-impaired listeners. A test-retest variability of 0.7 dB was found and the correlation between SRT and pure-tone average (PTA(0.5,1,2,4)) was 0.77. One month after launching the test, 20,000 calls were registered. It can be concluded that both versions of the newly developed test have steep slopes and small SRT differences across normal-hearing listeners. The screening test by telephone is highly reliable and proves to fulfill the need for an easily accessible and objective hearing screening.

This paper describes low-frequency auditory steady-state responses (ASSRs) to speech-weighted noise stimuli. The effect of modulation frequency was evaluated within the frequency range below 40 Hz. Furthermore, objective ASSR measures were related to speech understanding performance in normal-hearing and hearing-impaired listeners. The variability in ASSR recordings over independent test sessions was larger between subjects than within. Trends of increased responses around 10 and/or 20 Hz were found in all subjects. Obtained latency estimates of the responses pointed to primarily cortical sources involved in ASSR generation at low frequencies. Furthermore, significant differences between normal-hearing and hearing-impaired adults were found for ASSRs to stimuli related to the temporal envelope of speech. Comparing these responses with phoneme identification scores over different stimulus levels showed both measures increased with stimulus level in a similar way (rho=0.82). At a fixed stimulus level, ASSRs were significantly correlated with speech reception thresholds for phonemes and sentences in noise (rho from -0.45 to -0.53). These results indicate that objective low-frequency ASSRs are related to behavioral speech understanding, independently of level.

Two approaches to assess auditory steady-state responses (ASSR) are compared under similar test conditions: a monaural single-frequency technique with a detection method based on phase coherence (AUDERA), and a binaural multiple-frequency technique using the F-test (MASTER). ASSR thresholds at four frequencies were assessed with both methods in both ears of ten normal-hearing and ten hearing-impaired adult subjects, within a test duration of one hour. The test-retest reliability and the influence of prolonging the test duration are assessed. For the total subject group the multiple-frequency technique outperforms the single-frequency technique. In hearing-impaired subjects, however, both techniques perform equally well. Hearing thresholds can be estimated with a standard error of the estimate between 7 and 12 dB dependent on frequency. About 55% of the estimates are within 5 dB of the behavioral hearing threshold, and 94% within 15 dB. Prolonging the test duration improves the performance of both techniques.

The influence of test duration on the precision of hearing thresholds estimated by recording multiple auditory steady-state responses (ASSRs) was investigated. ASSR thresholds at four frequencies in both ears were assessed in 10 normal-hearing and 10 hearing-impaired subjects. The precision of the estimated hearing thresholds was compared for ASSR recordings of 5, 10 and 15 min per intensity level, corresponding to total test durations of approximately 30, 55 and 70 min for hearing-impaired ears. Furthermore, an intensity step size of 10 dB was compared to a step size of 5 dB. The mean difference scores averaged over the four frequencies were 15 +/- 10, 12 +/- 9 and 11 +/- 8 dB after recordings of 5, 10 and 15 min respectively. The corresponding Pearson correlation coefficients were 0.93, 0.95 and 0.96. Increasing the length of the separate recordings increases the precision of the estimates, independent of tested frequency. A compromise between both will have to be made. With a total test duration of approximately 1 h, four hearing thresholds in both ears can be estimated with a standard error of the estimate of 8 dB.