Screening audiometry – Welch Allyn TM286 Auto Tymp - User Manual User Manual

Page 11

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Directions for Use

Introduction

7

individual's acoustic reflex threshold level. Also, since the instrument uses a hand-held
probe and noise from hand motion can be detected by the instruments circuitry, the
magnitude of a detectable response must be somewhat higher than the criterion
generally used during clinical acoustic reflex threshold testing to avoid artifact caused by
hand motion. The acoustic reflex measurements made with this instrument are referred
to as screening acoustic reflex testing. The purpose of these screening reflex tests is to
determine whether a reflex is detectable rather than to determine the lowest intensity at
which the reflex occurs (i.e., threshold testing).

Screening audiometry

While tympanometry and acoustic reflex measurements check the integrity of the middle-
ear system, audiometry provides a means for checking the integrity of the entire auditory
pathway. Screening audiometry provides a method to determine an individual's ability to
hear a test signal at a particular intensity level or at the lowest possible intensity level
without the use of masking.

During screening audiometry, the test signal is generally presented through an earphone
to the ear. Different screening test protocols define the frequencies and intensity
sequence to be used to obtain a response. Audiometric testing requires a behavioral
response from the individual being tested. This consists of having the individual raise a
finger/hand or press a handswitch (optional) whenever the test signal is heard. The finger/
hand is lowered or the handswitch is released when the test signal is no longer audible.
The individual being tested must be able to understand a set of simple instructions and
have the ability to provide some physical sign when the test signal is heard.

The TM286 allows for both manual and automated audiometry. For further details on
automated audiometry, see

“Automatic Hearing Level”

on page 29 of this guide.

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