Concept Creep: When Psychological Terms Expand Beyond Their Meaning
What happens when clinical concepts stretch into everyday life, and how that shift both helps and harms how we understand mental health
Whether it’s conversations with family and friends, or overhearing strangers when I’m out and about, I regularly hear clinical language casually referring to psychiatric, psychological, and emotional disorders. Someone forgets to reply to a message and puts it down to ADHD. A colleague rearranges the items on their desk and claims that it’s their OCD kicking in. Anxiety is said to be off the scale before a presentation.
The vocabulary of "therapy speak” is increasingly becoming the vocabulary of everyday life. People talk about being triggered by a film, gaslit by a partner, traumatized by a meeting, surrounded by narcissists at work. Terms that were once the careful language of clinicians and researchers now show up in text messages, group chats, and throwaway comments at the checkout.
The aim of this article is to explore what’s lost or gained when words move from a diagnostic manual into the ordinary flow of how we explain ourselves, each other, and the world around us. In doing so, I’ll examine the findings of researchers who study this phenomenon, in particular the work of psychologist Nick Haslam who coined the phrase concept creep to describe the gradual expansion of psychological terms into territory they were never originally meant to reside.
Concept creep
Haslam, a professor of psychology at the University of Melbourne, published the paper that introduced the term in Psychological Inquiry in 2016.
The paper examined six concepts in detail: abuse, bullying, trauma, mental disorder, addiction, and prejudice. In each case, Haslam argued, the concept’s boundary had stretched in two distinct directions. He called the first direction horizontal creep, where a term extends outward to cover qualitatively new phenomena. He called the second vertical creep, where a term extends downward to cover less severe versions of what it already covered. Trauma, the case that draws the most attention, is a useful worked example. In mid-twentieth-century psychiatry, trauma referred to physical injury, and then to a severe psychological response to events outside ordinary human experience, like sexual assault, torture, or combat. Over subsequent decades, the term has stretched horizontally to cover forms of shared and inherited suffering (cultural trauma, intergenerational trauma) and vertically to cover milder and more subjective experiences. Both movements are what Haslam means by concept creep.
The three terms I mentioned at the start, ADHD, OCD, and anxiety, aren't among Haslam's six concepts. His case studies focus on harm-related terms specifically. The phenomenon I'm exploring in this article, clinical language moving into everyday life, is broader than concept creep as Haslam originally defined it. But his framework remains the most useful lens psychology has for thinking about what's happening, and it's where the strongest evidence lies.
From the research to everyday life
Bullying is the clearest case of horizontal creep in Haslam’s paper. When psychologists referred to bullying in the 1970s, the term described aggressive behavior among children that was intentional, repeated, and perpetrated from a position of power. Over the following decades, Haslam documents, the term expanded outward into contexts its original meaning wouldn’t have covered: adults at work, not just children in school, where it now covers persistent mistreatment, exclusion, and undermining conduct between colleagues.
The scale of that expansion shows up in the research itself. Haslam reports that between 1990 and 2010, citations to bullying research increased roughly a hundredfold. In occupational and organizational psychology journals specifically, articles on workplace bullying rose from 1.3 percent of output in the 1990s, to 8.8 percent in the 2000s, to 10.8 percent in the 2010s. This is concept creep in action: a term coined for one setting, with one specific set of behaviors in mind, now doing work across a much wider territory, at significantly more severe, less severe, and qualitatively different levels.
That pattern, a term leaving its original setting for a much wider one is exactly what we’re seeing now in everyday language. Jessi Gold, a psychiatrist at the University of Tennessee, told the American Psychological Association’s Monitor on Psychology that this isn’t a purely new phenomenon. People used to say “schizophrenic” to mean changing your mind and “OCD” to mean pay attention to detail. What’s changed, she argued, is that an emotionally aware generation with more access to the vocabulary has amplified a pattern of colloquial use that has always been there.
So is this bad, or is it good?
The question this raises is whether concept creep is something to be worried about.
On the critical side, the case is that broadened concepts do real damage. They dilute the clinical precision that exists for a reason. They can keep people stuck in self-diagnosis instead of seeking evidence-based care. They can minimise the suffering of people with serious conditions, by widening the category so much that the specific weight of the most severe cases is lost. Writing in Psychology Today, professor of psychiatry, Dr. Brendan Kelly describes the clinical stakes plainly: access to services, insurance coverage, educational support, and workplace accommodations often depend on diagnoses meaning something specific. When the language loses its edge, the systems that rely on it lose theirs too.
On the supportive side, the case is that broadened concepts are often well-motivated and have genuine benefits. Haslam himself makes this point in his 2016 paper. Concepts of harm that have broadened often recognise suffering that was previously ignored. They extend professional care to people who would once have received none. They give moral legitimacy to victims whose experiences didn’t have a name. And they promote treatment and sympathy over neglect and blame. The clinical psychologist Erin Parks, offers the clearest worked example. For most of history, she points out, a lot of people in abusive situations didn’t have the word “abuse” available to them, which made them more likely to blame themselves, to be confused by what was happening, and to see their situation as one they had caused rather than one they needed to escape. Language, Parks argues, can be powerful precisely because a term that seems obvious now wasn’t always there.
Neither side of this debate is a fringe position, and neither side has been settled by evidence alone. The rest of the article looks at what the research has to say about the specific claims that come up most often in the argument.
Has the DSM really been lowering its bar?
One of the most cited claims in Haslam’s 2016 paper, concerning concept creep and mental disorder, relates to the increased listings within the Diagnostic and Statistical Manual of Mental Disorders. The DSM, published by the American Psychiatric Association, is the reference book that lists the conditions clinicians are trained to recognize, sets out the criteria for each one, and standardizes the language clinicians, researchers, insurers, and educational systems use to talk about them. The current edition is the fifth, text-revised in 2022, and is among the most widely used mental health reference books in the world. Haslam pointed out that the manual had grown from 47 conditions in the 1940s to over 300 by the early 2000s.
If the DSM has grown that much, an obvious question to ask is whether it has lowered the bar for what counts as a disorder across editions, to the extent that the diagnostic criteria themselves have become looser over time? This is essentially what critics of diagnostic expansion have argued for decades; most notably Allen Frances, who chaired the task force that produced the fourth edition in 1994 and later wrote a 2013 book titled Saving Normal on the medicalization of ordinary life. The question of bar lowering hadn’t been properly tested, until Haslam and his co-author Fabiano decided to test it themselves.
In 2020, they published a meta-analysis in Clinical Psychology Review, which is a formal statistical method for combining results across multiple studies. They combined 123 of them, each one comparing how the same groups of patients were diagnosed under different editions of the DSM from the 1980s onward.
The headline result was that “the average risk ratio was 1.00, indicating no overall change in diagnostic stringency from DSM-III to DSM-5.” In plain English: across the manuals the meta-analysis was able to compare, the number of patients being caught under a diagnosis was just as likely to go down in a new edition as up. An equal number of conditions had become stricter as had become looser.
That result is not the whole story, and the authors are careful to say so. For specific conditions, diagnostic criteria have genuinely widened, enough that rates of diagnosis really have risen as a consequence of the manual changing rather than the underlying population changing. ADHD is one of them. Autism and eating disorders are others. The position Fabiano and Haslam set out is that the DSM has not been systematically loosening its criteria across the board, but individual conditions have moved in meaningful ways, some widening and some tightening. What the meta-analysis tests is one specific claim about the DSM, not the broader question of whether concept creep is driving diagnostic change, or the other way around.
Does using broader concepts of mental illness stop people from getting help, or encourage it?
If Fabiano and Haslam’s meta-analysis complicates one central claim on the critical side of the debate, another strand of research complicates the critical view from a different direction entirely. In 2021, Jia-Yan Tse and Nick Haslam published a study in Frontiers in Psychology looking at the relationship between how broadly people think about mental disorder and how positively they feel about seeking help for it.
The study compared 212 Asian American and White American adults recruited through an online platform. Each participant was asked to consider a range of experiences that might or might not qualify as mental disorder, and the researchers used their responses to measure how broadly each person drew the concept. They also measured help-seeking attitudes and stigma. The specific question Tse and Haslam set out to answer was whether differences in concept breadth might help explain a well-documented gap in help-seeking between the two groups: by external estimates cited in the study, Asian Americans are two to five times less likely than their White peers to seek mental health help.
What the analysis found was a mediation relationship. On average, Asian Americans in the sample held narrower concepts of mental disorder than White Americans. Those narrower concepts were themselves associated with less positive help-seeking attitudes. And the concept-breadth gap between the two groups accounted for a meaningful portion of the help-seeking attitude gap between them. In a mediation analysis, that pattern is the statistical fingerprint of one variable partially explaining the relationship between two others. Tse and Haslam also found a weak but present negative relationship between broader concepts and stigma: the broader the concept, the less stigmatizing the attitude.
The authors are careful about what their finding does and doesn’t establish. Their design was cross-sectional, which means they measured everything at one moment, and they write explicitly that this “does not allow inferences about the direction of associations.” It’s possible that broader concepts lead to more favorable help-seeking attitudes; it’s equally possible that people already inclined to seek help develop broader concepts along the way, or that a third factor is driving both. They also measured attitudes rather than actual treatment uptake, which they note makes it risky to assume concept breadth translates into real differences in who gets help and who doesn’t. And they stress that Asian Americans in the United States are a diverse group with varied ethnicities, immigration histories, and acculturation levels, so the study can’t be used to make broader claims about Asian cultures or Western cultures generally. The most the paper supports is that within this specific sample, concept breadth varied across two cultural groups and was associated with differences in help-seeking attitudes.
It’s a finding that proposes that broader concepts of mental disorder might, for some people, open a door rather than dilute a category. The door is real. The dilution is real. Both can be true at once.
What happens when someone is actually taught a broader concept
None of the research discussed in the article so far can tell us what happens to an individual person when they actually learn to think about a mental health concept more broadly.
In 2022, Payton Jones and Richard McNally set out to test exactly that. They published an experimental study in Psychological Trauma: Theory, Research, Practice, and Policy in which 293 adults were recruited through a crowdsourcing platform commonly used for research and randomly assigned to one of two conditions. One group was taught a broader definition of trauma; the other was taught a narrower one. Both groups were then shown a distressing clip from the Hollywood film The Last King of Scotland, and asked to report on their experience of it. In the days that followed, the researchers also checked back in with participants about any lingering distress.
What the paper found was a pair of results that only make sense together.
The first result came from measuring people’s pre-existing beliefs about trauma, before any teaching had taken place. Participants who already held broader concepts of trauma were more likely to classify the clip as a personal trauma, reported more intense negative emotions while watching it, and reported more event-related distress in the follow-up days after. Taken on its own, that finding would seem to suggest that broader concepts of trauma leave people worse off.
The second result came from the experimental arm of the study. The randomized teaching manipulation worked: participants assigned to the broader condition did come to hold broader concepts of trauma than those assigned to the narrower one. But the manipulation’s effects on the other outcomes, including emotional response and follow-up distress, were weaker and more indirect. The authors describe this as “limited support for causality.” Namely: the pre-existing correlation was real, but deliberately teaching someone a broader concept did not reliably worsen their experience of the clip in the same way that already holding one had.
The authors themselves flag a possible reading of this pair of results. It could be the case that a third variable, one they weren’t able to measure directly in this study, is driving both halves of the pattern. Trait anxiety is their suggested candidate. A person who is more anxious by temperament may already be more inclined to hold broader concepts of trauma and also be more vulnerable to distressing material. If that’s what’s happening, the correlation between broader concepts and worse outcomes isn’t caused by the concepts at all. It’s a shared symptom of something else.
The authors acknowledge the study’s limitations. Some of the scales they used were new and have not been tested extensively for validity. The sample was modest in size, mostly Caucasian, and entirely English-speaking. Their conclusion is a call for further research rather than a settled answer on either side of the debate.
The finding matters because it complicates the arguments on both sides. The critical view is partly right: broader pre-existing concepts do correlate with labeling more experiences as trauma and with stronger emotional responses. The supportive view is also partly right: teaching someone a broader concept, in a controlled setting, doesn’t reliably make them feel worse than teaching them a narrower one. And the authors’ own careful reading is that neither side’s simple story is the full one, because the correlation they found might be driven by something else entirely.
Concept creep and personal characteristics
If concept creep is a real cultural pattern, then individuals will adopt it to different degrees, and their personal characteristics may help explain who is most likely to drive it.
In 2019, Melanie McGrath and four co-authors, including Haslam, published a study in Personality and Individual Differences that set out to map those individual characteristics. They ran two studies with American participants recruited online, asking each of them to consider a range of borderline cases across four harm-related concepts (bullying, prejudice, trauma, and mental disorder,) and judge whether each case qualified. The researchers then looked at how concept breadth varied across different kinds of people.
The associations they found were broadly what Haslam’s 2016 framework would predict. People with broader concepts of harm tended to score higher on measures of empathic concern, tended to be more sensitive to injustice directed at others, and tended to hold more liberal political attitudes.
What the study didn’t find was arguably more interesting. A common perception is that younger generations have stretched the meaning of clinical language, while older generations have held on to more traditional, less expansive uses.
McGrath and colleagues found that age was not associated with concept breadth in their samples. Older participants were no more or less likely to hold broader concepts than younger ones.
As a case in point, I’m a Gen Xer and was definitely “triggered” by the video clip above. 😅
Why people reach for the broadened concepts in the first place
A really interesting take on this question comes from Ieuan Pugh, writing in The Psychologist in late 2025.
Pugh’s broader argument is about the wellness industry and how digital platforms commodify emotional experience. But within that argument, he makes an observation that sits at the heart of why language like this matters to the people using it.
I read this as part of a broader shift in which expressions of distress, and the language that carries them, are shaped by the dynamics of visibility and engagement. What emerges can lapse into a kind of therapeutic performance: emotionally resonant but shaped by commercial incentives.
For many, particularly those denied timely care, isolated by austerity, or failed by institutions, this offers something the state no longer reliably provides: recognition, validation, and a fragile sense of belonging. In a culture where solidarity has been systematically dismantled, loosely applied diagnostic labels often become one of the few available ways to feel seen.
Concept creep can dilute clinical precision. Broader pre-existing concepts can correlate with worse emotional responses. Specific diagnostic criteria have widened in ways that may genuinely inflate rates of diagnosis. But when the colleague says it’s their OCD, when the friend describes a meeting as traumatizing, when the relative calls a difficult ex a narcissist, they might be reaching for this language because something real needs naming and nothing better is available to them.
This article isn’t going to resolve that tension. The clinical concerns are real. The human reasons for this using this language are also real.
Final thoughts
I set out to write about this topic because I wanted to engage with what the research actually says, rather than with the noise that tends to surround it. Mental health is emotive territory. Any time someone’s suffering or someone’s language about psychological wellbeing comes into public view, the risk is that the conversation gets pulled quickly into culture-war positions where no one is really listening.
Haslam himself found that out. On the Therapy vs. The World podcast in 2024, he reflected that when he published his 2016 paper, he thought he had gone to great pains to be neutral. He was simply documenting that something was happening. What he got in response was readers assuming he was a reactionary, critics assuming he was invalidating people’s experiences, and, in his own words from the same conversation, being slotted into a culture-war identity he didn’t have.
That isn’t a reason to avoid writing about this kind of research. It’s a reason to be careful about how.
If the article has done anything useful, I hope it shows that the research on concept creep is more specific and more two-sided than a quick reading of the related issue of therapy speak tends to present. There are findings that should give critics pause. There are findings that should give supporters pause. There are gaps where the research hasn’t been done yet and questions the authors themselves flag as unsettled.
None of that offers the tidy, less nuanced position a culture-war debate can use and I’d like to think that’s exactly the point.
Here’s the podcast interview with Haslam mentioned above. It’s over an hour long and covers issues beyond the scope of this article, but it’s well worth listening to.
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What stayed with me is the tension you lay out at the end — that clinical concerns and human reasons for reaching for this language are both real. I think there might be a distinction hiding inside that tension that could help sort it.
From what I've observed, the same label can function in two different ways depending on what the person does with it after it lands. Used as a starting point — "I might have this tendency, so what do I do about it?" — it opens something. Used as a settling point — "I'm just like this, so it can't be helped" — it closes everything. The grammar is the same; the direction is opposite.
When labels are repeatedly used as settling points, they can gradually take on a functional role — less about describing an experience and more about shaping what others are expected to do. Not "I'm working on this" but "you must accommodate this." That shift can shrink the space for people who genuinely live with the condition, because the word has already been spent.
I offer this as an observation rather than a claim about prevalence. It seems useful to ask not only whether concepts have crept, but whether, for the person using them, the label remains a door they are walking through or one they've closed behind them.
This is a really thoughtful and balanced take, and I agree that something important is happening with the way psychological language is expanding. But I wonder if the focus on language itself misses a deeper layer. It’s not just that people are “overusing” clinical terms — it’s that they’re trying to name something they actually feel, often without having a more precise way to express it. So the question for me isn’t only whether concepts are stretching too far, but why those experiences are becoming so widespread that people reach for these words in the first place.
I also think it reflects a broader shift in people themselves. We’re not the same as we were even 50 years ago. What used to belong mostly to clinical or academic language now appears in everyday life, and that says something about the level of psychological awareness and development we’ve reached. As we evolve, our inner world becomes more complex, more layered, and in many ways more exposed. That often brings more psychological struggle, but also more attention to it.
There is simply more access now — to information, to frameworks, to conversations about the psyche — and people are actively engaging with it because they genuinely feel something that needs to be understood. So even if the language is sometimes imprecise, the need behind it is not. People are trying to make sense of their inner experience, and that requires naming it.