SISI
Pronunciation: SIS-ee
Also written as: SISI — Short Increment Sensitivity Index
A test that measures a patient's ability to detect small (1 dB) increments in intensity, used historically to identify cochlear versus retrocochlear pathology.
Full Definition
The Short Increment Sensitivity Index (SISI) presents a carrier tone at 20 dB SL upon which brief 1 dB increments are superimposed at regular intervals. Patients with cochlear hearing loss, due to recruitment, typically detect a high percentage of these increments (scores above 70%), whereas patients with retrocochlear or conductive pathology score low (below 20%). The SISI was a cornerstone of the site-of-lesion test battery before the advent of auditory brainstem response and imaging. In modern clinical writing, editors should note that SISI is largely superseded but still referenced in historical and comparative literature. The abbreviation should always be expanded on first use.
Usage
Usage note: Flag as a historically significant but largely obsolete test when editing contemporary clinical protocols; context should clarify its role in legacy test batteries.
In Context
- "A SISI score of 80% was obtained at 4,000 Hz, supporting a cochlear rather than retrocochlear site of lesion." — Archival audiological case study
- "Authors should note that the SISI test is rarely performed in modern practice and requires contextualisation when cited." — Editorial guideline for audiology journal submissions