A hearing test can help determine if hearing loss is present, if one or both ears are affected, the type of hearing loss, the degree of hearing loss, if the hearing loss can be treated medically or with hearing technology (e.g. hearing aids, cochlear implants, and assistive technology), and how this hearing loss will affect your child and his or her ability to communicate.
Different types of hearing tests
Hearing screenings
Hearing screening usually shows simply that a child’s hearing is not at a normal level. Screening procedures are fast, reliable, and painless. If a child fails a screening test, he/she will be referred for a more detailed assessment.
Objective hearing tests
These tests do not require your child to respond or participate when he or she hears a sound. These tests are generally used for infants and young children, children with developmental disabilities, children that will not cooperate, when other tests are inconsistent or unreliable, and to confirm results of behavioral testing.
- Auditory Brainstem Response (ABR) – A sound is played in the ears through earphones and the response to the sounds is recorded. These recordings are analyzed and provide an estimate of hearing sensitivity.
- Otoacoustic Emissions (OAEs) – OAEs provide information on the function of the sensory hair cells inside the hearing organ (cochlea). Sounds are sent into the ear with a small tip and a microphone records the response of the sound from the cochlea.
- Tympanometry – This type of test provides information on how well the eardrum and middle ear are working. A gentle puff of air is delivered into the ear and the amount the eardrum moves in response to change in air pressure is recorded. This test can help determine if there is a hole in the eardrum or if there is fluid in the middle ear.
Behavioral hearing tests
Behavioral tests provide information about how your child hears and responds to sounds across different pitches. Sounds are presented through headphones or speakers. The audiologist looks for and records your child's responses to the softest sounds presented and plots them out on a graph called an audiogram.
How hearing loss is measured
Sound occurs at different pitches called “frequencies” and at different loudness levels called “intensities”. The measurement unit for frequency is Hertz (Hz) and the measurement unit for intensity is the decibel (dB). The range of pitches that we hear includes low (250 Hz) and high frequencies (8000 Hz). The ranges of intensities that we hear are 0 dB (very soft sound) to 120 dB (very loud sound). A hearing test is a measure of how soft we hear at each pitch.
The audiogram
The results of a hearing test are written on a chart called an audiogram (a picture representation of your child’s hearing). The softest sounds that your child can hear are charted on the audiogram. Sounds can be soft or loud and low pitched or high pitched. Both the loudness and the pitch of a sound are shown on the chart. Very soft sounds are located at the top of the chart and very loud sounds are located at the bottom of the chart. Low pitches are on the left side of the chart and high pitches are located on the right side of the chart.
Degrees of hearing loss
The degree of hearing loss refers to the severity of hearing loss. For children, hearing is usually described by the average hearing level.
- Normal range or no loss: 0 to 20 dB
- Mild loss: 21 to 40 dB
- Moderate loss: 41 to 65 dB
- Severe loss: 66 to 90 dB
- Profound loss: 91 dB or greater
Hearing loss often affects our ability to understand speech. In particular, the consonants /p/, /k/, /f/, /h/ or all /t/, /sh/ and /s/ sounds are no longer heard.
Common questions related to hearing tests
Why does my child need a hearing test?
There a few different reasons why your child should have his or her hearing tested:
- Your child did not pass his or her newborn hearing screening or school hearing screening
- You, loved ones, or your child’s teacher has concerns that your child has difficulty hearing or following directions
- Your child reports that they have trouble hearing
- Your child is undergoing ear surgery
- Your child is starting medication that could affect hearing
How often does my child need to have a hearing test?
The status of your child’s hearing can change over time. Some hearing losses are temporary and can be treated medically while other hearing losses are permanent. Further, the severity of some hearing losses can change (either become better or worse) while other hearing losses remain stable overtime. Therefore, it is recommended that children with established hearing loss have a hearing test at least once a year to have a current picture of the child’s hearing. If your child is younger or hearing tests have been incomplete or inclusive this might require multiple hearing test appointments in a year.
Who will conduct my child’s hearing test?
A pediatric audiologist who is trained in working with infants and young children will complete a comprehensive hearing assessment. He or she will review the results of the assessment with you, answering any questions you may have, and explaining what the next steps are if needed in assessing and treating your child’s hearing loss.