The University of Southampton
University of Southampton Institutional Repository

Test-retest reliability of real ear measurements for open canal hearing aid fittings

Alaqrabawi, Wala' (2010) Test-retest reliability of real ear measurements for open canal hearing aid fittings University of Southampton, Institute of Sound and Vibration Research, Masters Thesis , 73pp.

Record type: Thesis (Masters)


When fitting hearing aids with conventional earmoulds using real ear measurements (REM) it is recommended to use the modified pressure with concurrent equalization method whereby a reference microphone is used to monitor the REM loudspeaker output level. The review of the literature indicates good test-retest reliability for REM using conventional earmoulds. However, in REM using open-fit, another sound field equalization method (the modified pressure with stored equalization method) should be used to minimize any inaccurate measurements resulting from the amplified sound leakage when the open-fit hearing aid is used. In addition the sound is delivered via a generic ear tip rather than a custom made earmould. Therefore, the test-retest reliability for conventional occluded earmould REM cannot be generalized to the open-fit measures.

Twenty otologically normal participants were tested to investigate short-term test-retest reliability for open-fit REM, and for conventional earmoulds at both 0o and 45o head-to-loudspeaker azimuths by performing repeated measurements at the same participant visit but after removing both the probe tube and the hearing aid and reinserting them. It was found that open-fit REM have good short-term test-retest reliability (mean 1.57 dB, SD 1.10 dB) at both azimuths and are in agreement with measured (mean 2.12 dB, SD 1.45 dB) and reported (SD ranged from 1 to 3.2 dB) conventional earmould REM test-retest variability values in the 0.25 to 4 kHz frequency range (Ringdahl A & Leijon A, 1984, The reliability of insertion gain measurements using probe microphones in the ear canal, Scandinavian Audiology, 13, 173-8). This finding is clinically significant as open fittings are widely fitted using REM to hearing impaired patients.

PDF P2704.pdf - Other
Download (1MB)

More information

Published date: 2010
Organisations: University of Southampton, Human Sciences Group


Local EPrints ID: 173763
PURE UUID: 8f0a46e2-7022-4de8-b067-77630266cab7
ORCID for Emma Mackenzie: ORCID iD

Catalogue record

Date deposited: 07 Feb 2011 12:02
Last modified: 18 Jul 2017 12:12

Export record


Author: Wala' Alaqrabawi
Thesis advisor: Emma Mackenzie ORCID iD

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton:

ePrints Soton supports OAI 2.0 with a base URL of

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.