Abstract
Background Hearing aid responses can be verified with the Real-Ear Aided Response (REAR). Procedures
for predicting the REAR from coupler-based verification exist, but have not incorporated
corrections for venting, limiting their use and validity for vented and open fittings.
A commercially available system for including venting effects in simulated real-ear
measurement (S-REM) has recently been developed.
Purpose To evaluate the accuracy of a vent-corrected S-REM for predicting the REAR across
test levels, for fittings with a wide range of coupling styles including modular domes.
Research Design This was a within-subject comparison study using technical measures. Retrospective
file review was used to obtain previously measured REARs from 104 fittings in 52 adults
and three hearing aid styles. Prospective data collection was used to re-measure each
fitting at three test levels using S-REM with and without venting corrections. Comparison
of differences by frequency band was performed to assess the impact of the venting
correction.
Results The vent model reduced low-frequency error by up to 11 dB, and the effects were consistent
with the expected effects of venting in hearing aid fitting: fittings with more open
dome or tip styles had a larger improvement when the vent model was added. A larger
sample of fittings was obtained for dome/sleeve couplings than for custom fittings.
Conclusions The vent-corrected S-REM system evaluated in this study provides improved fitting
accuracy for dome or sleeve-fitted hearing aids for adults and supports the use of
vented S-REM for open fittings. Further studies to examine a representative sample
of custom tip or mold fittings, and fittings for children are future directions.
Keywords
hearing aid - adult - verification - venting - coupler
