Audiogram The audiogram is a graphic representation of the results of a hearing test (audiometry). From the audiogram it is possible to read the hearing threshold at different frequencies.

Making an audiogram

To provide a detailed overview of the individual’s hearing ability, a number of different hearing tests must be made, including determining the hearing threshold for selected tones (frequencies). The hearing threshold is the level of intensity at which a sound is just audible to an individual. The result is plotted on an audiogram and compared with that of normal hearing to see whether the individual has a hearing loss.

The audiogram is an important tool in evaluating the individual hearing loss and fitting a hearing aid optimally.

How to read the audiogram

The vertical axis (y-axis) indicates the sound intensity – that is how soft or loud a sound is. Note that the scale starts with the weakest sound at the top. The unit of measure is decibel (dB).

The horizontal axis (x-axis) indicates frequency, with the lowest frequencies to the left and the highest frequencies to the right. Frequency is expressed in Hertz (Hz).

The shaded range at the top designates the normal range of hearing.

Normal hearing. If all measurements are in the shaded range, hearing is normal for all frequencies (see the figure for “normal hearing”).

Hearing loss. Measurements that fall more than 20-30 dB below the shaded range indicate a hearing loss. The lower the measurement falls, the higher the degree of hearing loss. The figure (see the figure for “hearing loss”) shows a hearing loss of 30 dB for the frequency 1,000 Hz.

The left ear values are marked with X (often blue)

The right ear values are marked with O (often red)

SEE ALSO:

Hearing test

Hearing threshold

Speech intelligibility

Frequency

Decibel