No abstract

No abstract

This paper reports the development of the Profile of Hearing Aid Performance (PHAP), a 66-item self-administered inventory that quantifies performance with a hearing aid in everyday life using both seven-score and four-score profiles. The profiles assess experience with amplification in terms of speech communication in three types of listening situations and in terms of reactions to amplified environmental sounds. The PHAP has been evaluated using groups consisting mainly of elderly hearing aid wearers having mild to moderate hearing impairments. Internal consistency reliability of the scales and subscales ranges from .70 to .91. Test-retest correlations range from .66 to .88. Ninety percent and 95% critical differences are presented to facilitate evaluation of differences between scores for the same individual under different conditions. It is envisioned that the PHAP will have its principal application in research evaluating and comparing different approaches to hearing aid fittings. In addition, the inventory can be used clinically to assess existing hearing aid fittings.

Intelligibility of conversationally produced speech for normal hearing listeners was studied for three male and three female talkers. Four typical listening environments were used. These simulated a quiet living room, a classroom, and social events in two settings with different reverberation characteristics. For each talker, overall intelligibility and intelligibility for vowels, consonant voicing, consonant continuance, and consonant place were quantified using the speech pattern contrast (SPAC) test. Results indicated that significant intelligibility differences are observed among normal talkers even in listening environments that permit essentially full intelligibility for everyday conversations. On the whole, talkers maintained their relative intelligibility across the four environments, although there was one exception which suggested that some voices may be particularly susceptible to degradation due to reverberation. Consonant place was the most poorly perceived feature, followed by continuance, voicing, and vowel intelligibility. However, there were numerous significant interactions between talkers and speech features, indicating that a talker of average overall intelligibility may produce certain speech features with intelligibility that is considerably higher or lower than average. Neither long-term rms speech spectrum nor articulation rate was found to be an adequate single criterion for selecting a talker of average intelligibility. Ultimately, an average talker was chosen on the basis of four speech contrasts: initial consonant place, and final consonant place, voicing, and continuance.

Frequency-importance and transfer functions for the Auditec of St. Louis recordings of the NU-6 word test are reported. The functions were derived from the word recognition scores of 24 subjects with normal hearing who were tested under 128 conditions of filtering and talker-spectrum-matched noise. The importance function was broader and had a lower midpoint than the NU-6 importance function reported by Schum, Matthews, and Lee (1991), but still displayed a bimodal shape. The transfer function was steeper than the transfer function reported by Schum et al., but comparable in slope to the transfer function for low-context CNC words reported by Bell, Dirks, and Trine (1992). Results from a limited set of conditions presented in quiet suggest that the use of masking noise was partly responsible for the dissimilar importance and transfer functions obtained by Schum et al. and this study. Differences in the equipment used in each experiment and in the methods used to analyze the data appear to have contributed as well.