PubMed HealthSearch

Biomedical subjects

D A Klodd

Publications and source records attributed to D A Klodd.

4 recordsLinked to original sources

Half-list speech discrimination measures in hearing aid evaluations.

The usefulness of half-list speech discrimination tests for evaluating hearing aids was assessed. Test and retest speech discrimination scores (SDSs) were obtained from 23 adults with moderate hearing impairment using four preselected hearing aids. Reliability coefficients were generally lower for half-lists than for full-lists, and the rankings of the hearing aids on the basis of SDSs were less consistent for the half-lists than for the full-lists. Individual subject differences between half-list SDSs were 10% or greater in more than one third of the cases. It was concluded that half-lists derived from the NU-6 full-lists should not be used to differentiate among hearing aids.

Adult

Occlusion effect: bone conduction speech audiometry using forehead and mastoid placement.

The occlusion effect (OE) was determined for bone conduction speech reception thresholds (SRTs) in 24 normally hearing subjects using forehead and mastoid placement. Results indicated that the OE was about 3 dB greater using forehead as opposed to mastoid placement. The intersubject variability of the OE is similar for the forehead and mastoid positions. The formula for effective masking for bone conduction speech should be equal to the minimum masking level for bone conduction speech plus the air-bone gap of the nontest ear plus 18 dB to account for the OE when using mastoid placement.

Acoustic Stimulation

Occlusion effect in bone conduction pure tone and speech audiometry.

Two experiments were conducted to determine the occlusion effect (OE) for pure tone and spondee stimuli. Results of experiment I using mastoid placement and unilateral occlusion yielded a mean OE for bone conduction speech reception thresholds of 4.67 dB, which was in agreement with the average OEs of 0.50, 1.0 and 2.0 kHz, or simply the same as the OE for 1.0 kHz. However, the magnitude of the observed OEs for test frequencies of 0.25 to 4.0 kHz was considerably less than the OEs reported in previous investigations. In an attempt to explain this discrepancy, experiment II used unilateral and bilateral occlusion with mastoid and forehead placement for pure tone stimuli. Significant differences (p less than 0.05) were found between OEs obtained with mastoid versus forehead placement and for unilateral versus bilateral occlusion.

Adult