J Am Acad Audiol 2022; 33(05): 277-284
DOI: 10.1055/a-1808-1275
Research Article

Venting Corrections Improve the Accuracy of Coupler-Based Simulated Real-Ear Verification for Use with Adult Hearing Aid Fittings

Susan Scollie
1   National Centre for Audiology, Faculty of Health Sciences, Western University, London, Ontario, Canada
2   School of Communication Sciences and Disorders, Faculty of Health Sciences, Western University, London, Ontario, Canada
Paula Folkeard
1   National Centre for Audiology, Faculty of Health Sciences, Western University, London, Ontario, Canada
John Pumford
3   Audioscan, Inc., Dorchester, Ontario, Canada
Parvaneh Abbasalipour
1   National Centre for Audiology, Faculty of Health Sciences, Western University, London, Ontario, Canada
Jonathan Pietrobon
3   Audioscan, Inc., Dorchester, Ontario, Canada
› Author Affiliations
Funding Ontario Research Fund, RE08-072


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.

IRB Approval

Received 20 Dec 2019 (Protocol 114746).


Any mention of a product, service, or procedure in the Journal of the American Academy of Audiology does not constitute an endorsement of the product, service, or procedure by the American Academy of Audiology.

Publication History

Received: 16 September 2021

Accepted: 17 March 2022

Accepted Manuscript online:
24 March 2022

Article published online:
07 November 2022

© 2022. American Academy of Audiology. This article is published by Thieme.

Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA

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