5
Examples of audiometric testing
5.1
Testing the older child or adult patient
5.1.1
Assessing pure tone threshold using the Hughson/Westlake procedure
Threshold
This is the lowest level at which the patient responds to the stimulus at least 50% of the time.
1. Talk to the patient while you walk him/her to the booth. This will give you some idea of how well he/she is hearing.
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Ask him/her which ear is his/her better hearing ear.
2. Perform otoscopic inspection of the ear canals to make sure that the ears are free from occluding cerumen (earwax) or
debris.
3. Optional: Perform tympanometry and reflexes prior to audiometric test.
4. Properly place the earphones. Begin the test with the air conduction transducer.
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If you are planning to test high frequencies, use the HDA 300 earphones for all frequencies (if it has been cal-
ibrated for all frequencies).
5. Give the patient the responder(s).
6. Instruct the patient so that he/she knows what to expect: "You will hear various sounds from low pitches to high
pitches. Push the button when you hear a sound, even if it is very soft."
7. If the patient reports having tinnitus, consider using a pulsed tone for testing.
8. Make sure that the control panel of the Otosuite software is set to the correct transducer and desired routing, sound
level, and frequency. Make sure that threshold test (THR) is selected.
9. Begin the test in the ear reported as the better hearing ear.
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Tell the patient in which ear the test will begin.
10. Start the testing at 1000 Hz.
11. Start presenting the tone at a sound level that should be clearly audible to the patient to confirm that instructions for
responding were understood.
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Present the tone for 1 to 2 seconds.
12. If the patient responds to the initial sound level presented, proceed with the test by decreasing the level in 10 dB
steps until no response is obtained.
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Increase the level in 5 dB steps until a response is obtained again.
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Continue decreasing in 10 dB steps and increasing in 5 dB steps until you determine the lowest level at which the
patient responds correctly to two of three trials. This is the threshold.
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Once threshold is obtained, store the response.
13. Continue testing with this up/down procedure in the following frequency order: 2000, 4000, 8000, 500, 250, 125,
and reconfirm the threshold at 1000 Hz.
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If there is a 20 dB difference or greater between octaves, test the interoctave frequencies.
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Talk to the patient occasionally. Encourage the patient to concentrate on the task. This will keep your patient
from getting bored or becoming an unreliable responder.
14. Switch to the other ear and tell the patient to listen for the sounds in that ear.
Madsen A450
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5 Examples of audiometric testing
