R 17A User’s Manual – Page 85
4.3 Autothreshold Audiometry
The automatic threshold test, in addition to manual testing, allows the automatic detection of the hearing
threshold by varying the level of the stimulus based on patient’s response. R17A incorporates this patient
controlled automatic threshold test, complying with EN ISO 8253-1, in a 10 db decrease and 5 dB increase
procedure, without masking. This test is a procedure used to determine pure tone thresholds
automatically, based on patient’s response at each frequency, through pressing on patient’s button,
connected to the device via nimi-USB socket (9).
How to conduct the test: the patient needs to be instructed on how to use patient’s button. The patient
will be asked to keep the button pressed when he hears the stimulus and release it when he no longer
hears the stimulus.
Test execution
Press the TONE AUTO icon (see adjacent image) on main menu to enter the Auto-threshold
Audiometry test.
Stimulus configuration
Press the STEADY button to change the type of signal to be emitted: continuous, pulse (2 Hz
rate), warble. At every click on the button, the icon changes identifying the type of signal.
Press the START icon to start the test, automatically the device will generate a 40 dB HL 1 KHz
stimulus. The frequencies will change according this sequence 1, 2, 4, 8, 1, 0.5 e 0.25 kHz; only
the frequencies enabled in the setup page will be used.
Test starts with a pure tone at 1000 Hz (40 dB HL) presented for 3 seconds with the purpose to train the
patient. Intensity will be increased in 5 dB steps and decrement of 10 dB steps.
When the patient releases the pushbutton (stimulus no longer heard), the automatic threshold detecting
procedure starts by presenting pure tones with a duration of 1.5 seconds and random interruption time.
When the minimum level (at which the patient is no more able to hear the sound) has been reached, the
level is increased and the first valid response is stored in the audiogram as the threshold.
During the test, intensity, frequency and patient response are shown on display
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