Trauma is a part of a person, not the whole of them.

A note to fellow clinicians to consider the risk of overshadowing in neurodivergence.

I have noticed a pattern that continues to reoccur across healthcare, not just mental health services. I believe it important to name and to write about it as a peer to other clinicians, particularly those currently focused on the assessment and diagnosis of neurodiversity.

For many clients, their journey broadly follows a similar pathway, something like this… A client presents with anxiety, mood instability, sensory sensitivity, exhaustion and relational difficulty. A trauma history surfaces during history-taking. A reasonable working formulation forms, with trauma at the centre. Treatment proceeds. The question of underlying neurodivergence is often not explored, or it gets raised and parked, or it surfaces years later in another service after several rounds of treatment that did not produce the expected response.

To read it in black and white, we can easily recognise this for what it is: diagnostic overshadowing of neurodivergence by trauma. However, in practice it can be insidious. This particular brand of diagnostic overshadowing has been, and continues to be, documented in the literature, with measurable consequences. In my own observation across wards, emergency departments, crisis services, primary care and now neurodiversity assessment services, it continues. And, although this is experienced by both men and women, it disproportionately affects women.

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A documented mechanism

The term ‘diagnostic overshadowing’ describes the clinical event where the clients’ presenting symptoms are misattributed to one feature of the clinical picture, rather than a separate or co-occurring condition. I understand that the term entered literature in intellectual disability research in the early 1980s. It has since been applied and documented across all healthcare settings, including mental health, autism and ADHD assessment contexts.

What is newer is direct experimental evidence that mental health professionals are vulnerable to a trauma-specific version of this bias. Wislocki and Zalta (2024) presented 232 mental health professionals with adult clinical vignettes. When a trauma history was present, professionals were more likely to assign a PTSD diagnosis and recommend PTSD-focused treatment, even when the presenting symptoms pointed elsewhere. A follow-up paper examined provider factors, highlighting that bias in diagnosis predicted bias in treatment. It also noted that older professionals tended to show greater error in both (Wislocki & Zalta, 2025).

Hold in mind that these studies did not test overshadowing of neurodivergence specifically. Rather, they tested overshadowing of OCD and substance use presentations by a disclosed trauma history. However, the principle they establish is a broader one in that once a clinician has trauma in their working model, that frame begins to do the explanatory work. Anything else that could fit tends to be overlooked, or absorbed entirely. It is through this frame that the inference to overshadowing of neurodivergence is reasonable. It is not directly evidenced by these experiments, and I am citing them on that understanding.

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Why women carry the heavier load

Diagnostic overshadowing in this area is not gender-neutral.

Autistic women especially have been documented repeatedly as receiving an autism diagnosis only after a series of mental health diagnoses that did not fit. McQuaid, Strang and Jack (2024) set out the structural pattern in a conceptual analysis in Autism in Adulthood. Female autistic presentations have historically been under-recognised because diagnostic frameworks were developed from predominantly male samples. Camouflaging and masking, both more common in autistic women, further reduce the chance of recognition. At the same time, the diagnostic criteria for borderline personality disorder can be applied in ways that capture autistic experiences such as emotional intensity, relational difficulty, identity uncertainty and self-injurious coping. The authors argue this produces a two-way bias, both against the diagnosis of autism in women, and toward the diagnosis of BPD in women. The two operate together.

Tamilson, Eccles and Shaw (2025) put patient voices to this pattern. Their phenomenological study in the journal Autism interviewed autistic adults previously diagnosed with BPD or EUPD. The participants were disproportionately female, a pattern the authors linked in part to gender bias in the initial labelling. One participant reported, “I think my diagnosis of BPD was purely based on the fact that I was self-harming”. Autistic shutdowns were re-read as dissociative episodes through a BPD lens. The misdiagnosis carried real harm to these women. Treatments aimed at reducing emotionally unstable behaviour can promote further masking, and masking is itself associated with poorer mental health and elevated suicidality in autistic adults.

None of this means men are immune to overshadowing. Male autistic and ADHD presentations are also missed, often routed instead through diagnoses of conduct disorder, antisocial features, substance use or anger management. Cultural pressures on men not to disclose vulnerability compound the risk. The male pattern is real and under described in the current literature, and it deserves its own attention. The structural disadvantage women face is becoming more recognised, documented, specific and dual-direction. Both patterns matter. They are not the same pattern.

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The differential diagnosis problem

These conditions look similar on the surface. Emotional intensity. Difficulty with relationships. Sensory dysregulation. Communication differences. Avoidance behaviours. Sarr and colleagues (2025) published a Delphi consensus study in the British Journal of Psychology that mapped this overlap of symptoms. One hundred and six international professionals reached consensus on 275 statements about the overlapping and differentiating features of autism, attachment disorders, complex post-traumatic stress disorder and emotionally unstable personality disorder. The authors framed the work explicitly around diagnostic overshadowing and misdiagnosis between these conditions.

The work highlights the need for clinicians to hold in mind that their task is not to choose between trauma and neurodivergence. Rather, it is to hold both questions open, often as co-occurring, and to assess each on its own terms.

A qualitative study by Ng-Cordell and colleagues (2022) helped to make the overlap more concrete. They recognised that coping strategies used by autistic individuals in response to trauma were sometimes indistinguishable from autistic behaviours. The authors then developed an explicit diagnostic overshadowing theme to capture this, namely that a behaviour read as a trauma response can be an autistic behaviour, and a behaviour read as autism can be a trauma response. They recognised and highlighted that the risk runs in both directions.

This is the point at which the reverse error needs naming. The argument here is not that all behaviour currently attributed to trauma is really neurodivergence. The opposite error happens too. Some adults arrive at a neurodivergence frame that does not fully account for what is happening either, and the assessment process must consider trauma, mental illness, attachment, medical contributors and substance involvement on their own terms. The clinical task is not to substitute one full account for another. It is to keep multiple questions alive.

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What I have observed across services

The published evidence describes the structural pattern. What I have witnessed across private and NHS wards, emergency departments, crisis services, primary care and neurodiversity assessment fills in the texture.

A note on what the next paragraphs are and are not. The patients I have seen are by definition a selected sample of people who arrived to services in distress, and within that group, often the ones for whom previous interventions did not produce the expected response. I do not see the women for whom trauma treatment worked and the neurodivergence question either was not relevant or never came up. The pattern I describe here is what crosses my caseload, not what the general population looks like. It is also not uniformly negative. Many of the patients I have worked with have had at least some clinicians who heard them well. Whether the next clinician will be one of those can feel, from the patient's perspective, like a lottery.

It is within this selected sample that I notice certain things recur.

Women typically come to me having concluded, often quite firmly, that they are the problem. They have been told they are treatment-resistant. They have been told their childhood adversity explains the whole picture. They have been told their persistent sense of difference is a symptom of trauma, or of personality structure, and that the work is to integrate this rather than ask further questions about it.

When I ask whether anyone has explored the possibility of autism or ADHD, or even learning differences and conditions such as dyslexia, dyspraxia, dyscalculia and dysgraphia, the answer is often that the question was raised and dismissed. Sometimes by the woman herself, who was told her symptoms were too mild, or too obviously trauma-based, or that women do not really present this way. Sometimes by a clinician who said the trauma had to be addressed first, and the neurodivergence assessment was then parked and did not come back.

What I have heard repeatedly, from patients across all of these service settings, is that the experience of their own description of their life is treated as further symptom, or ignored. When a patient says she feels the trauma account does not explain everything, that observation is sometimes received as resistance, denial, or insight deficit, rather than as additional relevant data. Patients have words for this. Unheard. Unseen. Gaslit. Those are the words I have heard used by patients in ward rounds, in primary care consultations, in crisis intake and in neurodiversity assessments. The consistency of that report across services and across years is in itself clinical information.

This is not a claim that all clinicians do this all the time. It is a claim that the pattern is common enough, across enough services, to be a structural rather than an individual issue. Time pressure, undertraining in neurodivergence, the dominance of stabilise-trauma-first protocols, burnout, and the historical maleness of diagnostic frameworks all contribute. Most of the clinicians involved in the pattern would not recognise themselves as biased. The pattern exists anyway.

This is a topic that is broad, diverse and complex and deserving of continued exposure, challenge and evolution.

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Trauma is a part of a person, not the whole of them

This is the core position I hold in my clinical work, and it is the position I would like to see held more widely amongst my peers.

Trauma is real. It deserves serious treatment. Accurate diagnostic assessment of neurodivergence often requires a baseline of safety and stability that trauma treatment helps create. None of what I am arguing is an argument against treating trauma first when clinical priority dictates it. The argument is narrower. Treating trauma first is not the same as treating only trauma. The neurodivergence question should remain on the table during, after, and alongside trauma work, rather than be closed before it is fully opened.

An incomplete formulation carries a cost

A trauma history does not explain why a person has always experienced the world the way they have. It does not explain lifelong sensory sensitivity. It does not explain the developmental signature of social communication differences. It does not explain executive functioning patterns that have been present since early childhood. A formulation that treats trauma as the whole story is an incomplete formulation, and the patient often knows this.

When that incomplete formulation is then defended against the patient's own observations of herself, the cost is not abstract. It compounds the original trauma. It deepens negative self-belief. It creates a layer of clinical injury on top of the lived injury that brought the person into services in the first place.

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Practical considerations for assessment

Three things, all small, that could change what is possible in a clinical encounter.

First, when a trauma history is disclosed during a neurodivergence assessment, or in any other clinical contact where neurodivergence might be relevant, treat it as additional information rather than as an alternative explanation. Both questions remain open. Trauma and neurodivergence frequently co-occur. In late-identified women, they often do.

Second, look for the pervasive, persistent and problematic developmental signature. Lifelong patterns are the strongest indicator that a presentation is not solely trauma-derived. Useful markers include sensory threshold differences present in early childhood (food, clothing, noise, light, touch); social communication patterns visible in school reports or remembered by family; executive functioning patterns evident in academic history, including organisation, transitions and task initiation; attentional profiles documented before any identifiable traumatic event; and the client's own narrative of feeling different from peers from a young age, often well before any adverse experience. None of these is diagnostic in isolation. Together, they constitute a pre-trauma footprint that trauma alone does not produce.

Third, listen to the patient when she tells you that the trauma account does not explain everything. She is often right. The clinician who is willing to hold the second question open, whether this could also be neurodivergence, is often the first who has done so.

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What this piece does and does not claim

I am a firm believer that honesty about the argument's limits matters more than rhetorical force.

This blog is my clinical reflection that is supported by the published literature. It is not a systematic review. The cited evidence establishes the mechanism of trauma-related diagnostic overshadowing in mental health professionals, the documented pattern of women being misdiagnosed with BPD or EUPD before being recognised as autistic, and the substantial overlap between autism, complex post-traumatic stress disorder and EUPD presentations. The Wislocki and Zalta experiments did not test neurodivergence as the target diagnosis. Their findings are extended to this context by reasonable inference. The McQuaid paper is a conceptual analysis rather than original empirical research. The Sarr paper is a Delphi consensus rather than direct empirical demonstration. The qualitative studies are descriptive and not generalisable in the statistical sense.

The cross-service observation reported here is drawn from my own clinical work. It is not a randomly sampled cohort. It does not establish prevalence. It establishes that the pattern is visible, consistent, and worth taking seriously across multiple service settings.

The reverse error, diagnostic overshadowing of trauma by neurodivergence, is also real. It is named here for that reason. The clinical task is to hold multiple questions alive in both directions.

The cost of not asking is borne by the patients who have already paid the highest price. The reverse cost, of asking too narrowly in either direction, is also real. The work is to hold the questions open and to take patients' own descriptions of themselves seriously as additional valid clinical data.

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References

McQuaid, G. A., Strang, J. F., & Jack, A. (2024). Borderline personality as a factor in late, missed, and mis-diagnosis in autistic girls and women: A conceptual analysis. Autism in Adulthood, 6(4), 401–427. https://pmc.ncbi.nlm.nih.gov/articles/PMC11861065/

Ng-Cordell, E., Rai, A., Peracha, H., et al. (2022). A qualitative study of self and caregiver perspectives on how autistic individuals cope with trauma. Frontiers in Psychiatry, 13, 825008. https://pubmed.ncbi.nlm.nih.gov/35911211/

Sarr, R., Spain, D., Quinton, A. M. G., et al. (2025). Differential diagnosis of autism, attachment disorders, complex post-traumatic stress disorder and emotionally unstable personality disorder: A Delphi study. British Journal of Psychology, 116(1), 1–33. https://pubmed.ncbi.nlm.nih.gov/39300915/

Tamilson, B., Eccles, J. A., & Shaw, S. C. K. (2025). The experiences of autistic adults who were previously diagnosed with borderline or emotionally unstable personality disorder: A phenomenological study. Autism. https://pmc.ncbi.nlm.nih.gov/articles/PMC11816473/

Webb, E., Lupattelli Gencarelli, B., Keaveney, G., & Morris, D. (2024). Is trauma research neglecting neurodiverse populations? A systematic review and meta-analysis of the prevalence of ACEs in adults with autistic traits. Advances in Autism, 10(3), 104–119. https://www.emerald.com/aia/article/10/3/104/1226251/Is-trauma-research-neglecting-neurodiverse

Wislocki, K. E., & Zalta, A. K. (2024). Assessing the existence of trauma-related diagnostic overshadowing in adult populations. Psychological Trauma: Theory, Research, Practice, and Policy, 16(8), 1367–1373. https://pubmed.ncbi.nlm.nih.gov/37053403/

Wislocki, K. E., & Zalta, A. K. (2025). Predictors of trauma-related diagnostic overshadowing bias. Behaviour Research and Therapy, 184, 104651. https://www.sciencedirect.com/science/article/abs/pii/S0005796724001785