Speech Audiometry - Interacoustics Affinity 2.0 Additional Information

2.0
Affinity Additional Information
There are many ways of applying clinical masking. Which method to use is your decision. Regardless of the
masking method channel 2 is used to occupy the better ear. In the example above channel 2 should be set
to Right (non-test ear) using the preferred masking stimulus preferred (usually Narrowband NB). Ensure that
Rev is ticked making the masking noise continuous. Channel 1 should be set to Left (test ear) using the
preferred stimulus (usually Tone). You can set the masking and tone level using the buttons on the screen,
the PC keyboard, or the dedicated keyboard. While trying to establish the true threshold of the left ear the
right ear is now distracted with noise.
When storing a threshold while the masking is enabled, the used masking level is stored in the masking table
under the ear that is being tested. The terms 'Effective masking' in this situation refers to the narrow band
noise level that was loud enough to effectively mask a pure tone of the indicated level heard by the
unmasked ear.
1.7.5

Speech Audiometry

Most people acquire hearing aids because they or their relatives report that they have trouble hearing
speech. Speech audiometry has the advantage of utilising speech signals and is used to quantify the
patient's ability to understand everyday communication. It examines the patient's processing ability in
relation to their degree and type of hearing loss which can vary greatly between patients with the same
hearing loss configuration.
Speech audiometry can be performed using a number of tests. For example, SRT (Speech Reception
Threshold) refers to the level at which the patient can repeat 50% of the presented words correctly. It serves
as a confirmation of the pure tone audiogram, gives an index of hearing sensitivity for speech and helps
determine the starting point for other supra-threshold measures such as WR (Word Recognition). WR is
sometimes also referred to as SDS (Speech Discrimination Scores) and represents the number of words
correctly repeated, then expressed as a percentage.
Note that there is a predictable relationship between the patient's pure tone threshold and speech reception
threshold. Speech audiometry may therefore be useful as a cross-check of the pure tone audiogram.
Required Items:
•
2.0
The Affinity hardware
•
Licensed AC440 Audiometry module within your Affinity
•
Headphones, insert phones, or free field speakers
•
A microphone, CD player or wave files
Test Procedure:
Before performing the speech audiometry you may wish to complete tone audiometry. This provides valuable
predictive information useful in the speech testing. Furthermore, the PTA level (Pure Tone Average) gives
you a basis for calculating the starting point for speech testing.
1) Open the AC440 module in the Affinity Suite through your patient management software, Noah or
OtoAccess™
2) Go to speech testing by pressing the Speech Screen button
3) If needed select a test protocol in the List of Protocols.
4) Select the input and output stimuli and intensity levels for channel 1.
If masking is needed, configure channel 2 also.
5) Explain to the patient that he/she will now hear some words/numbers/sentences though the ear
phones/free field speakers. Instruct him/her to repeat what is said even though it may be very faint.
Patients may also be encouraged to guess if they are unsure about the word/number/sentence. If
performing the speech test in noise do not forget to instruct the patient not to focus on the noise but on
the speech.
6) Start presenting the words, numbers, or sentences. Depending on the setup for speech testing (see
section 1.7.2.3) the test can be scored using the following buttons:
2.0
hardware
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