It's easy and only takes approximately 2 minutes to perform the Audible Contrast Threshold (ACT) test on Affinity Compact. Learn how to instruct your patient, how to do the actual test and how to use the ACT value for tailoring your client's hearing aid fitting.
You can read the full transcript below.
What is ACT?
The Audible Contrast Threshold test, also known as ‘ACT’, allows you to assess how well someone can hear in background noise. It does this by using a special signal that is non-language specific. ACT makes full use of the pure tone audiogram. Making this an above threshold test.
Required equipment
To perform ACT, you will need an audiometer with the ACT license, headphones or insert ear phones, a patient response button, and a completed binaural audiogram with thresholds stored for at least the following frequencies:
- 250 Hz
- 500 Hz
- 1 kHz
- 2 kHz
- 4 kHz
Performing ACT
Now we have everything we need; we can go ahead and perform ACT.
From the audiogram screen within the Affinity Suite, go to ‘Menu’, select ‘Tests’, and then click on ‘ACT’.
An instruction box will automatically appear.
Instruct your client on what they need to do, and make sure they understand to press every time they hear the special signal, which sounds like a siren.
Ensure that you have demonstrated the sound examples so that your client knows what to listen for.
Once your client is ready, click ‘Proceed to test’ and press ‘Start’.
As soon as you press ‘Start’, your client will hear episodes of noise.
The test starts at 16 dB nCL.
Press only once to deliver the siren at this intensity.
If the client hears the siren correctly, a black dot will automatically appear on the trace.
You continue performing the test in the same manner as pure tone audiometry.
Once a heard response has been stored, go down in intensity by two steps, and present again.
If the client does not hear the siren or does not respond to the sound in the correct timeframe, a white dot will appear, and you increase in intensity by one step.
This ‘two-down-one-up’ approach is the same as audiometry, and the test will automatically stop and store a value once it has reached three out of five correct responses.
Using the ACT value
Once the relevant number of correct responses has been reached to produce an ACT value, a green bar will appear in the middle of the screen.
You can now use this to counsel your clients about their ability to hear in noise.
Press on the ‘Guidance’ tab to reveal our recommendations for the different ACT severity levels.
Use this for counseling, to adjust hearing aids, to recommend assistive devices, and to discuss rehabilitation and communication strategies.
Selected hearing aid brands use the ACT value to automatically optimize their adaptive hearing aid features.
