The research, led by Kayla R. Steele and Jill M. Newby, examined fifty-nine adults whose primary diagnosis was social anxiety disorder. All of them completed an intensive form of internet-delivered cognitive behavioural therapy, or iCBT — a treatment format that condenses the principles of face-to-face CBT into a structured online program delivered over a shorter, more concentrated period rather than spread across many weeks. Intensive iCBT has become an increasingly important tool in mental health systems trying to close the gap between demand and available therapists, and trials of this format have generally shown that rapid symptom improvement is achievable without a clinician in the room. The Sydney team wanted to know whether a patient’s personality profile would influence not only how sick they were at the start, but how much they improved.

To answer that, the researchers turned to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, and specifically its Alternative Model for Personality Disorders, known as the AMPD. Rather than asking whether a patient meets a rigid checklist for a personality disorder, the AMPD describes personality pathology along two axes. The first is level of personality functioning, which captures how well a person maintains a coherent sense of self, regulates emotions and pursues meaningful goals, and how effectively they form intimate relationships, empathise with others and navigate social groups. The second is a set of maladaptive trait domains — negative affectivity, detachment, antagonism, disinhibition and psychoticism — that represent extreme, inflexible and harmful versions of normal personality dimensions. Standard questionnaires exist for both axes: the LPFS-BF for functioning and the PID-5-BF for traits, and both were administered at the start of treatment and again at its end.

Alongside these personality measures, participants completed well-validated scales for social anxiety — the Social Interaction Anxiety Scale and the Social Phobia Scale — as well as the Patient Health Questionnaire for depressive symptoms and the Work and Social Adjustment Scale for psychosocial impairment. Diagnostic interviews using the Anxiety and Disorders Interview Schedule for DSM-5 established the presence of social anxiety disorder and any comorbid major depressive disorder. This dual assessment structure meant the researchers could map the full landscape of personality pathology onto the symptom burden of each patient, and then track how that landscape changed as the therapy did its work.

The baseline findings were nuanced. On average, the group showed only mild impairments in personality functioning, and their maladaptive trait scores were largely in the non-clinical range — a striking result given that social anxiety disorder has historically been tightly linked with personality disorder diagnoses. However, the picture darkened considerably for participants who also carried a diagnosis of major depressive disorder. Comorbidity with depression was associated with greater impairment in personality functioning, echoing a large body of literature showing that depression tends to erode self-esteem, self-direction and interpersonal trust in ways that overlap with personality pathology.

Crucially, even within a sample that was not, on the whole, severely personality-disordered, the dimensional measures mattered. Greater impairment in personality functioning — particularly in the self-domain, which covers identity, self-worth and emotional regulation — was associated with more severe social anxiety symptoms. So too were higher levels of maladaptive traits, including negative affectivity, the tendency to experience frequent and intense negative emotions; disinhibition, reflecting impulsivity and difficulty with planning and restraint; and even psychoticism, the trait domain covering unusual thoughts and perceptual experiences. That such a broad sweep of trait pathology correlated with social anxiety severity suggests that the disorder does not simply ride on shyness or avoidance, but is embedded in a wider matrix of personality vulnerability that clinicians rarely measure in routine anxiety care.

The treatment findings, however, complicate the intuitive story that sicker personalities should mean poorer recovery. After the researchers statistically controlled for baseline symptom severity, personality pathology — both impaired functioning and maladaptive traits — no longer significantly predicted post-treatment levels of social anxiety, depressive symptoms or psychosocial impairment. In other words, once you know how severe a patient’s symptoms were before therapy, knowing their personality profile adds little independent information about how they will fare in the short term. This is an important message for an era in which personality pathology is sometimes treated as a contraindication for streamlined psychological treatments. The data here suggest that patients with social anxiety and mild-to-moderate personality difficulties should not be excluded from intensive iCBT on the assumption that their personalities will block progress.

Perhaps the most provocative result concerned change in the personality measures themselves. After the intensive program, participants showed significant reductions in both personality functioning impairment and maladaptive trait severity. Symptoms and personality moved together — which raises a deep theoretical question about causality and stability. The authors are appropriately cautious here, noting that these reductions may not be indicative of enduring personality change. Traits are conventionally understood as stable dispositions, and short-term improvements measured by questionnaires may simply reflect the lifting of anxious and depressive states that had temporarily inflated pathological responding. Distinguishing genuine trait change from state-dependent fluctuation would require longer follow-up, and this study did not establish that.

For the AMPD’s champions, the findings still count as a validation of sorts. The study demonstrated that the model’s dimensional components are clinically relevant in social anxiety disorder: they discriminate between more and less severe presentations, they flag comorbid depression, and they shift in parallel with treatment response. That a personality framework built for the personality disorders section of the DSM can illuminate a common anxiety condition supports the broader argument that personality pathology is better understood as a continuum woven through all mental disorders rather than a separate diagnostic silo. It also gives clinicians a practical vocabulary — self-functioning, negative affectivity, disinhibition — for describing the patients who struggle most, even when those patients fall short of a personality disorder diagnosis.

The study’s limitations are worth keeping in view. Fifty-nine participants is a modest sample, the trial was registered with the Australian New Zealand Clinical Trials Registry in March 2022, and the analysis lacked the long-term follow-up needed to say anything about durability. The authors themselves frame the results as preliminary. Yet the implications are concrete: personality assessment could help identify social anxiety patients who present with heavier symptom burdens, while reassuring clinicians that such pathology need not derail short-term digital treatment. As iCBT programs scale up worldwide, this kind of research helps answer the question that matters most in practice — not just who has the disorder, but who will get better, and why.

Subject of Research: Dimensional personality functioning and maladaptive traits in social anxiety disorder and their association with symptom severity and treatment response to intensive iCBT

Article Title: Personality functioning and maladaptive traits in social anxiety disorder: associations with symptom severity and change following intensive iCBT

Article References: Steele, K. R., & Newby, J. M. (2026). Personality functioning and maladaptive traits in social anxiety disorder: associations with symptom severity and change following intensive iCBT. BMC Psychology. https://doi.org/10.1186/s40359-026-05515-0

Image Credits: AI Generated

DOI: 10.1186/s40359-026-05515-0

Keywords: social anxiety disorder, personality functioning, maladaptive traits, AMPD, iCBT, DSM-5, cognitive behavioural therapy, negative affectivity, disinhibition, comorbid depression, digital mental health, BMC Psychology

The research team assembled a mixed sample of 955 participants drawn from Iran, combining 143 psychiatric patients who met DSM-5 criteria for somatic symptom and related disorders (SSRD) with 812 individuals from the general population who did not carry that diagnosis. The sample had an average age of 34.2 years, with a standard deviation of 11.5 years, and was 66 percent female. This design deliberately blended a clinically severe group with community participants, allowing the investigators to examine how somatization relates to other forms of psychopathology across a wide spectrum of severity rather than only within a narrow patient population.

Methodologically, the study took what the authors describe as a multidimensional approach. Participants completed a battery of self-report questionnaires covering somatic symptoms, psychological syndromes such as depression and anxiety, and two distinct ways of characterizing personality pathology. The first, criterion-based approach reflects the traditional categorical diagnosis of personality disorder, in which individuals are judged against diagnostic checklists. The second, trait-based approach follows the newer dimensional model, assessing maladaptive personality traits as continuous dimensions. By including both frameworks, the researchers could test whether the answer to their question depended on how personality pathology is defined — a critical check, because the field of personality assessment is currently in transition between these two paradigms.

To reduce the many questionnaire items to interpretable constructs, the team used exploratory factor analysis, a statistical technique that identifies clusters of variables that covary together and can be treated as underlying latent dimensions. This procedure extracted four factors corresponding to somatization, psychological syndromes, criterion-based personality disorder, and maladaptive trait-based personality pathology. In other words, the data themselves organized into the conceptual categories the researchers set out to compare, providing a clean foundation for the predictive analyses that followed.

The heart of the study lay in hierarchical linear regression, a technique that allows researchers to enter predictors in stages and measure how much additional variance each block explains. Here the logic was straightforward but powerful: if somatization were fundamentally a manifestation of personality pathology, then personality measures should explain substantial variance in somatic symptom reporting even after current psychological distress is statistically controlled. Conversely, if somatization is chiefly tied to present distress, the psychological syndromes factor should dominate. The results were unambiguous, and the effect sizes were striking.

Compared with criterion-based personality disorder, the psychological syndromes factor was far more strongly related to the somatization factor. The psychological syndromes accounted for an R-squared of 0.512, meaning they explained just over half of the variance in somatization scores, whereas criterion-based personality pathology explained only 0.105. In the hierarchical models, the incremental contribution — the change in R-squared — was 0.414 for psychological syndromes against a mere 0.007 for criterion-based personality disorder. The same pattern emerged when the trait-based model was used instead: psychological syndromes achieved an R-squared of 0.512 versus 0.138 for maladaptive traits, with incremental values of 0.377 versus 0.004. Whichever lens was applied to personality, the conclusion held.

The team also examined a single-item, pain-related measure as a separate outcome, and here too psychological syndromes outperformed both personality frameworks, though with smaller absolute effects. The syndromes factor explained an R-squared of 0.151 for the pain measure, compared with 0.067 for criterion-based personality disorder and 0.066 for trait-based pathology. The incremental contributions were 0.086 for psychological syndromes against 0.003 and 0.001 for the two personality approaches respectively. The authors are careful to note that these pain findings rest on a single-item indicator and should not be generalized to multidimensional assessments or to chronic pain conditions, where the underlying dynamics may differ considerably.

What do these numbers mean conceptually? The authors conclude that somatization appears to be a phenomenon primarily related to psychological distress rather than to personality pathology, and that this holds regardless of the theoretical context used to define personality problems. This does not mean personality pathology is irrelevant. The study found that both criterion-based and trait-based personality pathology were independently related to somatization, so the association is real. But when current psychological distress is taken into account, personality pathology shrinks to a marginal predictor. In practical terms, a patient’s present levels of depression, anxiety, and related syndromes carry most of the predictive signal for bodily symptom reporting, while personality structure adds only a thin residual layer of explanation.

The clinical implications are significant. Somatization is notoriously difficult to treat, and patients with somatic symptom and related disorders often consume substantial health care resources through repeated investigations and specialist referrals that yield little relief. If the strongest statistical lever for understanding somatization is current psychological distress rather than entrenched personality pathology, then interventions targeting distress — such as treatments for depression and anxiety — may offer the most direct route to reducing the burden of somatic symptoms. The authors explicitly frame their findings as a way to refine theoretical models and improve clinical outcomes by targeting the most impactful constructs, and the variance figures suggest that distress-focused constructs are precisely those impactful targets.

The study also carries methodological lessons for the research community. Because the pattern of results was consistent across both categorical and dimensional conceptualizations of personality pathology, the conclusion is not an artifact of one diagnostic school. The use of factor analysis to establish latent dimensions before regression, and the hierarchical entry of predictors to isolate incremental validity, provide a template for similar comparative questions in psychopathology research. The work was approved by the ethics committee of the Mind GPS Institute of Kermanshah, Iran, conducted in accordance with the Helsinki Declaration, and supported methodologically by that institute without external funding. As with any cross-sectional, self-report study, causal direction cannot be established, and the general-population sample from a single country invites replication elsewhere. Yet the sheer size of the gap — psychological syndromes explaining roughly half the variance in somatization while personality pathology explains a tenth or less — makes this one of the clearer statistical verdicts the field has received on a long-standing debate, and it points clinicians firmly toward treating the distress, not just the personality, when the body speaks for the mind.

Subject of Research: The relative contribution of psychological syndromes and personality pathology to somatization

Article Title: Relative sensitivity of phenotypic personality pathology and psychological syndromes to somatization phenomenon: a multidimensional approach

Article References: Komasi, S., Macina, C., Miettunen, J., Nazari, A., Heydarpour, B., Shams-Alizadeh, N., & Amianto, F. (2026). Relative sensitivity of phenotypic personality pathology and psychological syndromes to somatization phenomenon: a multidimensional approach. Discover Mental Health. https://doi.org/10.1007/s44192-026-00615-0

Image Credits: AI Generated

DOI: 10.1007/s44192-026-00615-0

Keywords: somatization, somatic symptom and related disorders, personality pathology, psychological distress, DSM-5, hierarchical regression, factor analysis, maladaptive traits, pain, psychopathology, mental health, Relative