How are Audiometry Tests Interpreted?

an audiologist is reviewing a patient's audiogram

An audiometry test is a hearing test that aims at showing the health status of your hearing. These tests produce an audiogram, which is a graph that helps you visualize the results of the evaluation. Learning how to read and interpret this graph is essential to understand the severity of your hearing loss

Moreover, when you receive your results, you will be able to consult your expert audiologist who can help you find a suitable solution. In some cases, you will also be able to speak about and discover the different hearing aids at your disposal.

What does an audiogram look like?

The audiometry tests are evaluations designed to understand the severity of hearing loss and suggest suitable solutions. Such tests consist of exposing an individual to a range of sounds a healthy hearing can perceive, at different frequencies. This technique helps an audiologist gather enough information regarding how the hearing performs with different sounds. Usually, these tests are performed in extremely quiet environments, and the sound is delivered through headphones.

An audiogram will look like a grid that reminds of a piano keyboard. On the X-axis of the graph, you can find the frequency, from low pitch to high pitch. On the Y-axis, you will find the decibel (dB) at which the sound is produced, from high to low. 

Each quadrant of the graph will show:

  • Bottom right: Loud noise, high pitch
  • Bottom left: Loud noise, low pitch
  • Top right: Soft noise, high pitch
  • Top left: Soft noise, low pitch

Moreover, the graph will show two lines, a red and a blue one, which help plot the graph:

  • The red line: O represents the right ear.
  • The blue line: X represents the left ear.

How to read an audiogram

While an audiogram does not express a qualitative report of your hearing, it can also help detect hidden hearing loss. To read the audiogram, follow the lines as they perform across the graph and you will discover how you hear perceived the range of sounds you were exposed to.

When doing so, remember that the zero dB on the graph represents the softest sound audible by an average person through healthy hearing. Instead, the frequency (Hz) range usually goes from 125Hz-8,000Hz, although a normal conversation sound level generally within the 250-6,000 Hz bracket.
Symbols on an audiogram
Aside from the grid, axis, and colored lines, you can notice other symbols and letters scattered across the graph. 

The first test conducted is called air conduction test, because the sound travels through the air to your ears. These results are marked on the graphs with X’s and O’s, depending on the ear in question.

These generally represent the result of a bone conduction test usually performed after the first air conduction test. This evaluation involves an oscillator and aims at stimulating the mastoid bone, a bone behind the ear. 

These results can be seen plotted in the graph with either:

  • A blue or red triangle
  • Bracket depending on the ear in question

All the symbols on a graph are usually connected with a blue or red line to be easier to interpret. However, it is crucial to keep in mind that the red line refers to the right ear, and the left life refers to the left ear.
What is a normal hearing on an audiogram?
With a better grasp of how to read the results of your audiometry test, you might want to find out how severe your hearing loss is and if there is an underlying hidden hearing loss. 

Before approaching the graph, it is essential to understand that what is considered the normal hearing level of an average person with a healthy hearing is at the top of the graph. Indeed, the top horizontal band between -10 and 20 B represents the average hearing ability. If your results or part of your results fall under this category, your hearing is healthy.

However, it is common to see the lines on the graph turn into a slope as the frequency increases or decreases. You might notice your hearing to perform worse with sounds that have higher frequencies or vice-versa.

In this case, speaking to your audiologist is vital. Indeed, an audiologist can help you craft a plan of action to implement an adequate hearing aid solution for your situation. 

Learn more about Audiometry Tests by visiting our Pacific Audiology Clinic or call us at 503-719-4208.