To put it simply, malingerers are patients who pretend to be ill. Most clinicians have encountered at least one patient feigning illness, and the field of audiology is no exception. Luckily, you have the Stenger test and a handful of others in your armoury, so you won’t be at the mercy of the skilled or unskilled malingerer.
Usually, ‘fakers’ don’t have enough knowledge of the feigned illness or disability to be entirely convincing. So, they give themselves away all too easily. A skilled malingerer, on the other hand, is calm and rational. He or she avoids displaying strange behaviour or making exaggerated claims.
Be aware that there is a risk in exposing or trying to expose the patient’s charade. If you’re wrong, the consequences can range from an embarrassing apology to a lawsuit. If you’re right, embarrassment and lawsuits are still on the cards, albeit not your cards.
Let’s equip ourselves with some methods for determining whether a patient is faking it or not.
Why Would My Patient Try to Fool Me?
While external incentives may vary, they usually fall into one of two categories:
A patient may want to avoid military service, or try to conceal a disability to avoid losing his or her job. Convicted criminals might malinger to avoid lengthy prison sentences.
Patients may fake hearing loss to claim compensation, access a disability grant or as a way to obtain drugs they do not need. This is prevalent in occupational health audiometry.
Malingering in audiology is also known as:
- Non-organic hearing loss (NOHL)
- Functional hearing loss
- Exaggerated hearing loss
Understanding a patient’s possible motivation can be helpful when you suspect malingering. Before we step into diagnosing non-organic hearing loss, we have to determine whether or not there is any suspicion of malingering.
Red flags that suggest malingering:
- Is there a discord between responses to the clinician’s questions?
- Is the patient’s audiogram atypical, and are there any changes of threshold responses at the same frequencies in repeated examinations?
- Does a patient who is claiming profound functional hearing loss still respond to questions asked in a lower voice, especially when they cannot read your lips?
- Are air conduction thresholds worse than acoustic reflex thresholds?
- In speech audiometry, does the patient repeat only a part of the word presented? For example, half-word responses to spondees.
- Has the patient expressed an obvious interest in obtaining financial benefit?
- Is there inconsistency between PTA and SRT?
- Are bone-conduction results worse than air-conduction results?
While the above list is by no means a diagnosis, it is important to keep these points in mind when testing.
How to Diagnose Non-organic Hearing Loss
Diagnosing functional hearing loss must be performed through a thorough process of clinical examination and testing.
There are several tests available for the diagnosis of malingering. These tests are generally classified into two groups:
- Special subjective audiometry tests
- Objective audiometry tests
Specific tests for detecting NOHL are the Stenger test and the Lombard test. Objective testing includes Auditory-Evoked Potentials (AEP) and Otoacoustic Emissions (OAE).
Special subjective audiometry tests
THE STENGER TEST
The Stenger test is used to determine malingering in the case of unilateral hearing loss. The principle behind this test is based on Stenger’s discovery that if two sounds of the same frequency and slightly different intensity are played at the same time in both ears, the patient will believe that he or she hears the tone in the ear where the sound is louder.
A 10 dB sound is presented above the threshold in the good ear and a sound of 10 dB below the admitted threshold in the suspect ear (or poor ear).
A malingerer will claim that they cannot hear the tone presented as they are not aware that a sound was actually presented in both the good and the dysfunctional ear.
THE LOMBARD TEST
Here a patient is asked to read some text aloud while wearing earphones. While the patient is reading the text, a sound is emitted in the earphones.
Unaware of their natural response, the suspect patient will increase the intensity of their voice because of the loud sound played in the earphones. A patient with real (profound) hearing loss would not hear the noise and therefore not change the intensity of their voice.
While subjective tests are simple in theory, they are not easy to execute and are best handled by a skilled audiologist.
The Stenger test and the Lombard test are seldom used in occupational health where inconsistent test results should be directly referred to an audiologist. Objective tests can detect real thresholds which make them more reliable and are often preferred in these cases.
Objective audiometry tests
OTOACOUSTIC EMISSIONS (OAE)
The principle of OAE is that the normal ear generates sounds that can be recorded. The presence of these sounds indicates whether the cochlear has normal or near normal functionality.
OAEs, especially transient-evoked otoacoustic emissions (TEOAEs), have been shown to be of value in cases of nonorganic hearing loss. However, these tests do not work as well for patients with actual hearing levels greater than 40 dB HL, who wish the clinician to believe that their hearing is worse than that.
AUDITORY-EVOKED POTENTIALS (AEP)
AEP measurement has long been considered an important test in the diagnosis of non-organic hearing loss. Results obtained from this technique and from voluntary pure-tone testing generally agree within 10 dB.
Auditory evoked potentials and auditory brain-stem response (ABR) have proven to be more reliable than the auditory middle latency responses or the auditory late responses in detecting non-organic hearing loss.
Objective measures do not require the cooperation of the patient and are therefore a highly recommended way of catching a would-be malingerer.
The problem is that this specialised equipment for objective testing does not come cheap. While objective testing is clearly the preferred methodology, many practices simply cannot afford it.
How the Kuduwave can help pick up malingering
While malingering is not an everyday occurrence, it does happen and requires vigilance. This is especially true in the field of occupational health audiometry or industrial audiometry, where patients could stand to benefit from false claims, or pose a risk to themselves and others by remaining untreated.
With the Kuduwave, you can carry out patient-response monitoring.
This is where the use of a response button in audiometry has a massive advantage over raising your hand.
By monitoring and tracking patient response times and accuracy down to the millisecond, we are able to distinguish between false and true responses as well as provide analyses of the patient’s response times.
With this data attached to every report and available on the live audiogram screen, a clinician can make informed decisions based on a true representation of the patient’s test results, and provide the ability to detect malingering on the spot.
Find out more about patient response statistics.
What to Do If You Identify Malingering
As specialists in this field, most of us have experienced a patient faking it. If you haven’t, it’s probably only a matter of time until you do.
If a thorough investigation shows a patient to be malingering, you may decide to confront the patient. In this case, avoid direct accusations. A thoughtful approach, that asks the patient to clarify inconsistencies, is likely to be safer and more productive for the examiner.