The Stenger test uses the auditory phenomenon ‘The Stenger Principle’, which states that a person will only hear the louder of two identical tones presented to both ears at the same time. The test is useful in patients with a suspected unilateral non-organic hearing loss, also known as malingering.
You can perform the test with two tuning forks, but we recommend using a two-channel audiometer for better accuracy.
Malingering a hearing loss is when a patient does not respond to the stimuli on purpose. This causes an audiogram that shows a hearing loss without this being the case.
It is hard to say why a person may choose to fake a hearing loss. The cause can be psychological, such as the need for attention. It can also be driven by motive, such as hearing loss compensation.
Whatever the cause or motive, the Stenger test is a good test to identify malingering.
[1] The audiogram is completely flat.
[2] The thresholds keep moving up and down.
[3] The audiogram shows a large hearing loss, but the patient does not have any problems hearing you when you speak.
Given ‘The Stenger Principle’, you perform the test by presenting tones to both ears at the same time. Set the intensity level to 10 or 20 dB above the threshold in the good ear and 10 or 20 dB below the threshold in the poor ear. Keep the intensity level in the good ear fixed while increasing the intensity in the poor ear in 5-dB steps. The point at which the patient responds in the poor ear will allow you to plot the extent of the non-organic component.
20 dB above/below threshold is used in Figure 1.
Figure 1: Stenger test example with a two-channel audiometer.
The speech Stenger test is identical, but with the use of speech material instead.
Instruct your patient the same way as you would do with standard pure tone audiometry.
Do not tell your patient that the stimulus is presented to both ears at the same time.
If the hearing loss in the poor ear is genuine, the patient will keep responding to the signal presented to the good ear (negative Stenger).
If the patient is simulating the hearing impairment, he/she will not respond to the stimuli. This shows that the tone presented to the poor ear is louder than the patient’s actual threshold (positive Stenger).
The Stenger test is a useful test for quick identification of a unilateral non-organic hearing loss.
It also avoids challenging the patient, as you can move seamlessly from standard pure tone audiometry into the Stenger test without the patient knowing.