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Validity and repeatability of level-independent HL to SPL transforms
S D Scollie1, R C Seewald, L E Cornelisse
1Hearing Health Care Research Unit, School of Communication Sciences and Disorders, University of Western Ontario, London, Canada.
Ear and Hearing
|October 31, 1998
Summary
The real ear to coupler difference (RECD) and real ear to dial difference (REDD) reliably predict real ear sound pressure levels (RESPL). These measures offer a valid alternative to in situ audiometry for hearing aid fitting.
Area of Science:
- Audiology
- Acoustics
- Hearing Science
Background:
- Accurate measurement of sound pressure levels in the ear canal is crucial for hearing aid fitting and audiological assessments.
- Traditional in situ measurements can be time-consuming and may be influenced by factors like probe tube placement.
- The real ear to coupler difference (RECD) and real ear to dial difference (REDD) are established methods for estimating ear canal acoustics.
Purpose of the Study:
- To evaluate the reliability and validity of RECD and REDD in predicting real ear sound pressure levels (RESPL).
- To determine if these measures can serve as substitutes for in situ audiometric procedures.
Main Methods:
- Measurements of RESPL, RECD, and REDD were conducted on 24 normal-hearing subjects.
- Probe microphone equipment was used with both insert and supra-aural earphones.
- Measurements were repeated after removing and replacing the earphones and probe tube to assess reliability.
Main Results:
- RECD and REDD demonstrated high and equal reliability and validity in predicting RESPL.
- RECD was used for insert earphones, and REDD for supra-aural earphones, in the prediction models.
- Test-retest differences for RECD and REDD indicated high reliability.
Conclusions:
- RECD and REDD are reliable and valid predictors of RESPL.
- These measures can be utilized as level-independent hearing loss to sound pressure level transforms.
- RECD and REDD offer a viable alternative to in situ audiometric procedures, simplifying audiological assessments.
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