Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Graduation

Spring 5-6-2011

Document Type


Degree Name

Doctor of Audiology (AuD)


Department of Communication Sciences and Disorders


Ayasakanta Rout

Lincoln C. Gray

Dan C. Halling


Real-ear measurements have been proven to be the most accurate measure of hearing aid verification. However, many audiologists find real-ear to be too time consuming to use consistently. One popular reason for underutilizing real-ear verification is the use of first fitting algorithms provided on manufacturer programming software. However, the predicted fittings provided on the software are not an accurate means of providing what is recommended by popular prescriptive formulas (Hawkins and Cook, 2003; Aarts and Caffee, 2005). The main reason for this discrepancy is that the software does not take into account individual anatomical differences, i.e. ear canal volume and impedance. When performing real-ear insertion gain (REIG), one must take into account individual differences by measuring the unaided response of the ear canal. When using REIG, prescriptive targets can be chosen which display the appropriate amount of gain recommended based on your patient’s amount of hearing loss and natural ear canal properties. While the real-ear method of target matching has been proven to be the most accurate means of hearing aid fitting, little research has been done to determine if there is a quantifiable benefit to this method. The purpose of this study is to examine the effects of utilizing REIG throughout hearing aid fittings and adjustments. In particular, are there any differences in speech understanding in quiet and noisy conditions? Also, is there any difference in the amount of benefit the patient feels they are receiving from their hearing aids or how satisfied they are with them? Eight subjects were tested on measures of HINT Quiet and Noise, APHAB and SADL; measures were done before and after programming was matched to NAL-NL1 targets using real ear verification. Findings indicate that programming hearing aids more closely to prescribed targets did not necessarily correlate with improved speech understanding and patient-perceived satisfaction and benefit. However, patient feedback indicated that the preference was to have targets matched to prescriptive gains as closely as possible.



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