Episode 1 of The Trauma Therapy Space podcast: forensic psychologist Dr. Grant Blake on how to assess symptom validity, and why it matters in everyday trauma treatment.
How do you know whether a client's symptoms are genuine? In the first episode of The Trauma Therapy Space, Dr. Suzy Matthijssen and Sander Kamphuis talk with Dr. Grant Blake about malingering: the intentional exaggeration or fabrication of symptoms for an external benefit.
Grant is a clinical and forensic psychologist from the Sunshine Coast, Australia, and a court expert in criminal and family law. He wrote his PhD on fitness to stand trial, has supervised PhD research on malingering, and in 2024 founded an intensive trauma treatment centre based on the Dutch model. Above all, he calls himself a passionate trauma therapist.
Here are the key insights from the conversation.
What is malingering?
Malingering is when someone intentionally exaggerates or fabricates mental health symptoms, cognitive impairment or a level of disability to gain something from it. That gain is always external: access to ADHD medication, disability funded support, an insurance payout, or avoiding prosecution or a heavier sentence.
It is often confused with factitious disorder, which used to be called Munchausen syndrome. In both cases people exaggerate or fabricate symptoms, and in factitious disorder they may even induce them. The difference lies in the motive. People with factitious disorder are driven by an internal need for care, sympathy and support, and it is a diagnosable mental illness. Malingering is not.
Grant also describes a subtler form called false imputation. Here the symptoms are real, but the person deliberately points to the wrong cause. Someone may have PTSD from childhood abuse, for example, but claim it was caused by a car accident. The deception is not about the symptoms, but about where they came from.
How common is malingering?
The honest answer is that nobody knows exactly. Malingering involves deception, so intention is hard to prove, and there are no reliable prevalence studies. What can be measured is how often people fail validity tests, and that depends heavily on the setting and on what is at stake.
Grant shares some estimates to give a sense of scale. Among tertiary students being assessed for ADHD, it is estimated that up to about 40% may exaggerate or fake their symptoms to obtain medication, compared with around 18 to 20% among non-students. In criminal law evaluations the estimates sit around 20 to 25%, and in high stakes cases, such as those in the US where a death sentence is possible, they rise further.
The way people deceive also shifts with the context. In family law, people usually want to come across at their best, so if they do malinger, it often takes the form of a sympathy maximisation strategy: presenting as a good person who has been badly harmed. Sometimes it even works the other way round. Applicants for police jobs, for instance, tend to deny the everyday memory slips that almost everyone has.
How do experts assess symptom validity?
According to Grant, a reliable assessment never rests on a single source. It starts with a clear understanding of the referral question and with collateral information. In forensic work that means reading police documents and previous reports, because you never walk into an evaluation without knowing the background.
In the interview itself, he approaches the person as if he knows nothing. He asks for long, open narratives and listens for what is consistent and inconsistent, both within the story and compared with the collateral. He also asks himself whether the presentation fits what we know about the condition: how it usually looks, how it develops and how it responds to treatment.
Then comes psychological testing, which Grant considers essential. Research shows that an interview or mental state examination alone is not reliable for picking up exaggerated or fabricated symptoms. Broad instruments such as the MMPI-3 look at symptoms and response style at the same time. But a test result is never the final word. Test failure can have other causes, so everything needs to be weighed together.
Suzy experienced this first hand. Convinced she could convincingly play a severe PTSD patient, she took Grant's test and failed clearly. She was pan-feigning: endorsing almost every symptom across the board, which makes a feigned profile much easier to recognise.
Above all, Grant stresses the right mindset. "Whenever you approach these evaluations, you have to be curious, but you can't be on the lookout for a liar." Wrongly labelling an honest person as a malingerer can be devastating. When the evidence is not strong enough, he chooses more careful wording, describing a presentation as inconsistent or unreliable rather than calling it malingering.
Why symptom validity testing belongs in trauma treatment
One of the most practical points in the episode is that symptom validity testing is not just a forensic tool. In clinical settings, most people are honest and will pass. That is exactly what makes testing at the start so useful. When treatment does not progress as expected, clinicians sometimes begin to wonder whether the symptoms are genuine. If validity was checked at intake, that question has already been answered, and the doubt never enters the therapy room.
At Grant's trauma centre, every patient is screened. The tests are built into the intake forms, so they cost the clinicians no extra time. And failing a test does not automatically mean being turned away. The team first looks at which tests were failed, how strongly, and what else could explain the result. The patient then receives short, structured feedback and a second chance with a different instrument, such as the MMPI-3. Only when both rounds are clearly failed is treatment declined. Intensive, exposure based trauma treatment simply requires a clear and confirmed diagnosis, so the whole team knows what they are treating and why.
Grant has also seen what happens without this step. He has supervised therapists who discovered, after years of treatment, that a client had been feigning PTSD all along. They were heartbroken, because the therapeutic relationship they believed they had built had never really existed.
Why people lie, and what that means for clinicians
The conversation also takes a more human turn. Everyone lies, Grant points out. Lies help us get what we want and avoid what we don't. For people who grew up without food on the table, without safety or affection, lying can be a highly adaptive survival strategy. In forensic work he sees how this disadvantage builds up over a lifetime, sometimes starting even before birth.
The painful irony is that people who end up in the justice system are often punished more harshly for using the very coping strategy that once protected them. Seeing lying as functional behaviour, rather than a character flaw, helps clinicians stay curious and compassionate.
It is emotional work for the professional too. Being deceived by a client can trigger anger, frustration or self-doubt. Grant remembers an early case in which a client on day release from prison gave him completely dishonest accounts for months, while the prison held information it had never shared with him. He was angry with the prison, upset with the client, and frustrated with himself for not picking it up. His advice to clinicians is to notice those reactions, set them aside, and keep returning to the facts and the test results.
The takeaway
Malingering is rarer in clinical settings than in court, but that is precisely why it deserves attention in trauma treatment. A careful, curious approach, combining background information, open interviewing and validated tests, protects both your clients and the quality of your work. And checking symptom validity at intake means you can focus fully on treatment, without doubt creeping in later on.
Frequently Asked Questions
What is the difference between malingering and factitious disorder?
Both involve deliberately exaggerating or fabricating symptoms. In malingering the motive is an external reward, such as money, medication or a lighter sentence. In factitious disorder the motive is internal: a need for care and sympathy. Only factitious disorder is a diagnosable mental illness.
Can a clinical interview detect malingering?
Not reliably on its own. Interviews are important, but they are not sufficient to detect exaggerated or fabricated symptoms. Validated symptom validity tests are needed, combined with background information.
Does a failed validity test mean someone is malingering?
No. Test failure can have other causes, and people may present differently with different evaluators. A conclusion requires multiple measures pointing the same way.
Should trauma therapists test every client for symptom validity?
Grant's trauma centre does. Short screening tests built into intake forms take no clinician time and give clarity from the start.
What is pan-feigning?
Endorsing almost every symptom across many domains at once, such as psychiatric symptoms, cognitive impairment and depression. Because the profile is so extreme, it is relatively easy to detect.
Listen to the full episode
In the full conversation, Grant also talks about the difference between assessment and long term therapy, the MMPI-3 versus the PAI, and some very Australian stories involving sharks and a carpet python.
Score your practice in 2 minutes
This episode is all about one question: does the picture really add up? Ask the same about your own practice. How much of your week goes to notes, which tools do you rely on, and where could AI make a real difference?
Answer 9 quick questions about your week, your notes and your tools. About two minutes, no client information needed.
