Audioscan Verifit - Manual (Page 88)

Verifit ® User's Guide Version 3.12  May 2015
4. Highlight and <PICK> REUR (below REAR/REIG test 3).
5. Press <Continue> to accept the default 55 dB SPL Pink noise stimulus and capture the REUR curve OR
highlight and <PICK> [Stimulus] and [Level] to select other values. These choices have no impact on the
resulting REIG.
6. If there is a notch in the 4000 to 8000 Hz region, try advancing the probe tube 2 mm and repeating step 3. If
the notch moves to a higher frequency, repeat this step until the notch moves beyond the highest frequency
of interest.
Because it is analyzed in 1/3 octave bands, the Noise stimulus produces a REUR 12 dB below that produced by
the Swept stimulus at the same overall level.
The Average REUR used is shown above. Measured REUR will vary from this.
For small children the peak may shift to the right and become sharper. Drainage tubes and perforated ear drums
will cause large differences - usually around 1 kHz.
REAR measurement procedure
1. Press <Tests>, then highlight and <PICK> [On-ear measures], then highlight and <PICK> [Insertion gain].
2. Referring to On-Ear Measures - Setup and On-Ear Measures Screen Setup, prepare the system, position the
patient and insert the probe tube. (For tight-fitting hearing aids or earmolds, the probe tube may be inserted
through a vent.)
3. Without disturbing the probe tube, insert the hearing instrument or earmold.
4. Referring to Audiometric data entry, enter threshold data.
5. Highlight and <PICK> button 1, 2, or 3 in the REAR/REIG column. This will present a signal from the
sound-field speaker and display the REAR Setup box.
6. Highlight and <PICK> [Stimulus], then highlight and <PICK> [Pink noise] or [Swept]. Use pink noise when
using the NAL-NL1 fitting formula. Use Swept when testing maximum output capabilities.
7. Highlight and <PICK> [Level], then highlight and <PICK> a stimulus level from the list box. Use the level
shown on the target REIG curves (if present). If no level is shown, use the lowest level required to overcome
background noise.
8. Adjust the hearing instrument so that the REIG curve (SPL scale) or Aided threshold curve (HL scale)
approximates the dotted target curve. For multi-level targets, match each curve using the stimulus level
indicated.
9. Press <Continue> to complete the test and capture the data.
See Insertion gain in SPL and Insertion gain in HL for an explanation of screen curves. See SII calculation in
Insertion gain
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