GSI AudioStar Pro™ Clinical Audiometer
80
D-0100778 Rev C
SISI (Short Increment Sensitivity Index) Test
The SISI test is used to detect small intensity changes in a steady-state signal in
patients with disorders of the cochlea. The SISI tests a patient’s ability to detect 1
dB change of intensity in a pure tone stimulus at 20 dB SL. A SISI consists of 20
target intensity increments (200 msec at 1, 2, or 5 dB) presented every 5 seconds
and can be completed for a number of frequencies. The SISI test is scored in
terms of the percentage of correctly identified 1 dB increments out of a possible
20. Scores of higher than 70% indicate cochlear involvement equals Positive
SISI. Scores of less than 70% indicate auditory disorders not in the cochlea or
normal hearing equals Negative SISI.
Presentation Level
Increase the attenuator to
20 dB SL.
Test Instructions
“You will hear a steady tone in your left or right ear. There may be an increase
in loudness. Each time you hear the increase in loudness, press the patient
response button.”
Test Procedure
Familiarize patient by presenting an easily heard (5 dB) SISI step. To do
this, press the presentation bar one time per presentation of the SISI
increment.
Select
dB Step
(1 dB) for the test.
To begin, press the “
Interrupt
” button to automatically present the
intensity increment change every 5 seconds.
Observe
the
patient
responses
– Record them using the
“
correct/incorrect
” counter.
Press Store to record the SISI score for each frequency. Results are
displayed on the results table.
