Audioscan Verifit - Manual (Page 67)

Verifit ® User's Guide Version 3.12  May 2015
If the limit is exceeded during an on-ear test, the Verifit will terminate the test and display the message 'MAX
TM SPL EXCEEDED'. You must then decide to either reduce the maximum output limit of the hearing
instrument or increase the Max TM SPL setting following the steps above.
If the MAX TM SPL limit has been disabled, a notice will appear on each real-ear screen. Also, a message
reminding you that the MAX TM SPL limit has been disabled will appear when you select an on-ear test.
ABR nHL to eHL setup
Estimated Hearing Level (eHL): An estimate of the behavioral pure tone threshold that accounts for a
measured ABR threshold.
Normalized Hearing Level (nHL): (a) Stimulus peak-to-peak equivalent SPL (pe SPL) at ABR threshold
relative to the average stimulus pe SPL at ABR threshold of a normal-hearing jury OR (b) stimulus SPL at ABR
threshold relative to the average stimulus SPL at behavioral threshold of a normal-hearing jury for the same
stimulus. (Note that in this latter case, nHL is equivalent to eHL).
In Speechmap/DSL you have the option of entering ABR thresholds in either eHL or nHL. If eHL is selected,
the threshold is treated as if it were a behavioral pure-tone threshold. If nHL is selected, the entered data will
first be converted to eHL before SPL threshold and fitting targets are calculated. To do this, appropriate eHL to
nHL conversion factors must be applied. You can choose to apply default conversion factors or enter new ones
for each client.
This setup allows you to select the default conversion factors that are applied in Speechmap/DSL to convert
ABR nHL threshold to eHL threshold.
1. Press <Setup>, then highlight and <PICK> [ABR eHL to nHL].
2. Highlight and <PICK> [DSL defined] or [User defined]
3. For [User defined], enter conversion factors using a mouse, the keypad or a keyboard. See Assessment data
entry.
When using the barcode option, both entered nHL data and the nHL to eHL conversion factors are printed as a
single barcode. See Barcode data input.
Positioning the client
Sound reflections from nearby surfaces (including the operator) can cause large measurement errors, especially
if the client moves between REUR and REAR measurements. Room noise can increase test time, cause errors
and alter the operation of the hearing instrument being evaluated.
1. Choose a quiet location and position the client and the sound-field speaker at least 1.5 m (5 feet) away from
any hard surfaces.
2. Position the client directly in front of, and facing, the sound-field speaker at a distance of 45 to 90 cm (18 to
36 in.) from the center of the head.
3. Position the back speaker (if used) directly behind and facing the back of the client’s head so that front and
rear speakers are at the same height and are at the same distance from the center of the client’s head.
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