Correction Factors; Correction Factor Values - Interacoustics Eclipse Additional Information

Eclipse Additional Information

6.5.4 Correction Factors

1. Selected Correction allows you to select any available pre-programmed correction factor table can be
selected and its parameters will be displayed.
2. From Name of Correction you can enter the name of a new correction factor table you create yourself.
3. Press New to create your own correction factor table.
4. Press Save to save the new correction factor table.
5. Press Delete to delete the selected correction factor table.
6. Press Cancel to cancel current actions related to correction factor table changes.
7. ASSR to Audiogram Correction Factors: This is where you can enter the correction factors that will ap-
plied to the dB ASSR thresholds to arrive at the dB eHL of the Estimated Audiogram.
Please note with the release 1.2.6, the corrected eHL cannot exceed 0dB eHL.

6.5.4.1 Correction factor values

Hearing threshold measures in audiometry always have a rather large spread, not only between repeated
measures but also between normal hearing patients. This is not only true for normal psychophysical hearing
thresholds, but also when we attempt to estimate hearing thresholds based on an electrophysiological test.
The correction factor applied from nHL (electrophysiological threshold) to eHL (estimated hearing threshold)
also has a standard deviation.
The nHL to eHL corrections is dependent on the degree of hearing loss in such a way, that severe hearing
losses have a very small nHL to eHL correction, compared to normal hearing thresholds that has a much
larger correction.
These inaccuracies once in a while combine to offset the results in the same direction, in which case we can
arrive at a situation where e.g. 500 Hz TB or NB CE-Chirps in a normal hearing individual gets corrected to a
degree where the resulting estimated hearing threshold better than 0 dB.
In order for the values in such an example to be plotted in the audiogram format, this indication of normal
hearing is plotted by the system as 0dB eHL.
Where do the correction factors for nHL – eHL come from?
The correction factors used under ASSR version 1.2.3 have been collected by:
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