The instrument in question is the Hospital Anxiety and Depression Scale, or HADS, a fourteen-item questionnaire first developed in the 1980s by R.P. Snaith and A.S. Zigmond. Its genius lies in what it leaves out. Most depression questionnaires ask about fatigue, appetite loss, or sleep problems, but in a hospital ward or a diabetes clinic those symptoms may reflect the underlying illness rather than a mood disorder. HADS was deliberately designed to avoid physical symptoms, focusing instead on the emotional core of anxiety and depression, which is why it has become a staple in chronic disease settings around the globe. Until now, however, nobody had formally evaluated how well the Vietnamese version of the scale performs in adults with type 2 diabetes, leaving clinicians and researchers in Vietnam without clear guidance on how to interpret its scores.

To close that gap, a team led by Son Huynh of the University of Medicine and Pharmacy at Ho Chi Minh City recruited 465 adults with type 2 diabetes from three different outpatient diabetes clinics in Ho Chi Minh City. The multi-site design was not a luxury; it was a deliberate choice to see whether the questionnaire behaves consistently across different clinical settings, something single-site validation studies cannot reveal. Each participant completed the Vietnamese HADS along with the Patient Health Questionnaire-9, a well-established depression measure that served as a benchmark for comparison. The study was approved by the Ethics Committee for Biomedical Research at the University of Medicine and Pharmacy at Ho Chi Minh City, and all participants provided written informed consent.

The first question the researchers tackled was reliability: does the scale produce consistent, stable measurements? Using modern ordinal reliability coefficients, which are appropriate for the ordered response categories typical of psychological questionnaires, they found an ordinal McDonald’s omega of 0.765 for the anxiety subscale and 0.846 for the depression subscale. In practical terms, both figures fall within the range generally considered acceptable to good, meaning patients’ answers hang together coherently enough to support meaningful score interpretation. That is a foundational result, because no amount of sophisticated structural analysis can rescue a questionnaire whose items fail to measure anything consistently.

The deeper question was structural validity: does the questionnaire actually separate into the two distinct dimensions, anxiety and depression, that its design promises? The answer turned out to be more complicated than a simple yes. Exploratory factor analysis, guided by parallel analysis, initially suggested three underlying factors rather than two. But when the team inspected the third factor, they found it was fragmenting the depression items without representing a genuinely distinct psychological construct, so they retained the original two-factor solution. Confirmatory factor analysis then confirmed that two-factor structure, though only after the researchers incorporated two theory-driven correlations between residual terms, adjustments that account for overlapping wording in the Vietnamese translation. The final model showed acceptable fit, with a root mean square error of approximation of 0.084, a comparative fit index of 0.922, a Tucker-Lewis index of 0.904, and a standardized root mean square residual of 0.076.

The most technically sophisticated part of the analysis was a bifactor model, a statistical framework that asks whether a questionnaire is best understood as measuring one broad underlying dimension plus some specific subdimensions, or as several largely independent dimensions. The results were striking. A substantial general distress factor emerged, explaining a large share of the common variance: the omega hierarchical coefficient reached 0.839 and the explained common variance was 0.608. In plain language, most of what the Vietnamese HADS measures in this population is a single, broad current of psychological distress that runs through both the anxiety and depression items. At the same time, enough residual variance remained within each subscale to suggest that the anxiety and depression scores still carry some distinct, meaningful information beyond the general factor.

Construct validity testing added further nuance. Both subscales correlated moderately with the PHQ-9, supporting convergent validity, the idea that the scale is measuring something related to what similar tools measure. Discriminant validity, the ability of the two subscales to keep themselves statistically distinct, was supported for the depression subscale but not for the anxiety subscale. The square root of the average variance extracted for anxiety was 0.552, which fell below the correlation between the two subscales of 0.652. That means the anxiety and depression scores overlap so heavily in this population that they cannot be treated as cleanly separable constructs, echoing the bifactor finding that general distress dominates the measurement.

Perhaps the most practically important discovery came from an exploratory analysis of cross-site comparability. When the researchers compared item responses across the three clinics, three depression items related to anhedonia, the loss of interest or pleasure in activities, showed comparatively larger differences between sites, with eta-squared values ranging from 0.18 to 0.21. Those are sizable effects, indicating that responses to these particular questions varied noticeably depending on which clinic a patient attended. The authors caution that this heterogeneity means researchers should be careful when comparing or pooling HADS scores across different settings in multi-site studies, because some of the observed differences between sites may reflect measurement inconsistency rather than genuine differences in patient wellbeing.

So what should clinicians and researchers in Vietnam actually do with the Vietnamese HADS? The study’s conclusions are deliberately measured. The scale demonstrates acceptable structural validity and partial construct validity in Vietnamese adults with type 2 diabetes, and the bifactor results support the total score as a broad, cross-sectional index of general psychological distress. The authors recommend that the total score should be the primary measure reported, with the individual subscale scores offering useful but more limited supplementary information. Crucially, diagnostic accuracy and criterion validity, the ability of the scale to identify true clinical cases against a diagnostic gold standard, have not yet been established. The total score is therefore supported strictly as a continuous indicator of emotional burden for research and routine care, not as a formal screening or diagnostic tool.

The study also carries a broader lesson for global health measurement. Patient-reported outcome measures do not travel effortlessly across languages and cultures; every translation inherits quirks of wording, and every new clinical population can reshape how items behave. By combining classical reliability estimation, exploratory and confirmatory factor analysis, bifactor modelling, and multi-site heterogeneity checks, the Vietnamese team has modeled the kind of thorough validation that questionnaires deserve before they are used to inform care decisions. For the hundreds of millions of people worldwide living with type 2 diabetes, and for the clinicians trying to see beyond the disease to the person, having a distress measure that is trusted, transparent about its limits, and grounded in local evidence is a quiet but consequential step forward for mental health care in chronic disease.

Subject of Research: Psychometric validation of the Vietnamese Hospital Anxiety and Depression Scale in adults with type 2 diabetes

Article Title: Psychometric validation of the Vietnamese Hospital Anxiety and Depression Scale (HADS) in adults with type 2 diabetes mellitus: a multi-site cross-sectional study

Article References: Huynh, S., Pham, O., Nguyen, N., Phan, L., Le, T., Nguyen, V., & Pham, A. (2026). Psychometric validation of the Vietnamese Hospital Anxiety and Depression Scale (HADS) in adults with type 2 diabetes mellitus: a multi-site cross-sectional study. BMC Psychology. https://doi.org/10.1186/s40359-026-05608-w

Image Credits: AI Generated

DOI: 10.1186/s40359-026-05608-w

Keywords: HADS, type 2 diabetes, psychometric validation, anxiety, depression, Vietnam, bifactor analysis, psychological distress, patient-reported outcome measures, factor analysis, mental health screening, Ho Chi Minh City

The new research, published in the Journal of Eating Disorders, was conducted by Jessica E. Hocking of the Department of Psychology at the University of Notre Dame, now at Belmont University, together with Lucy Osler of Cardiff University’s School of English, Communication, and Philosophy and Michael C. Rea of Notre Dame’s Department of Philosophy. The collaboration itself is notable: rather than treating philosophy and psychology as separate enterprises, the team set out to determine whether a purely theoretical account of disrupted bodily experience could be translated into measurable constructs and validated with data from real participants. Their findings provide empirical support for phenomenological approaches to understanding anorexia broadly, and for Osler’s specific account of disrupted embodiment in particular.

At the heart of the study is the Disrupted Embodiment Scale, or DES, an instrument designed to capture the distinctive ways in which people with anorexia nervosa experience their own bodies. The scale is built around three dimensions drawn directly from phenomenological theory. The first, Body as Hardship, reflects the sense of one’s body as an encumbrance, a burden to be endured or managed rather than a home to be lived in. The second, Body as Threat, captures the feeling that the body is dangerous, something to be monitored, controlled and defended against. The third, Body as Separate from Self, describes a striking dissociative quality: the experience of one’s body as alien, as an object distinct from the person who inhabits it.

These dimensions matter because phenomenological philosophers have long argued that eating disorders are not simply about body image dissatisfaction or the desire to be thin. On Osler’s account, anorexia involves a deeper disruption in the pre-reflective, embodied relationship a person has with their own body. In everyday life, most people do not experience their bodies as objects at all; the body recedes into the background, quietly enabling action and experience. In anorexia, on this view, the body becomes foregrounded in a troubling way: it is experienced as an obstacle, a source of distress and something set apart from the self. The philosophical literature has articulated these ideas with care, but until now they had largely remained theoretical, lacking quantitative evidence that the described experiences actually distinguish people with anorexia from those without it.

To test the account, the researchers recruited two groups of participants. The first comprised 220 undergraduate women, a general population sample. The second comprised 138 women who self-identified as currently experiencing anorexia nervosa. All participants completed cross-sectional online questionnaires assessing disrupted embodiment, body dissatisfaction, drive for thinness, bulimic behaviors, general eating disorder symptomatology, dieting behaviors and impairment due to eating disorders. This design allowed the team to ask two distinct questions: whether disrupted embodiment contributes something beyond the well-established risk factors of body dissatisfaction and thinness-idealization, and whether women with anorexia actually report the kinds of experiences the phenomenological literature predicts.

The answer to both questions was, with one exception, yes. Using hierarchical multiple regression analyses, the researchers found that the DES total score and its three subscales explained variance in eating disorder symptomatology, bulimic behaviors and eating disorder-related impairment above and beyond body dissatisfaction and drive for thinness. In other words, knowing how much a person experiences her body as a hardship, a threat or as separate from her self adds predictive power beyond the traditional measures that dominate the field. This is a significant result, because it suggests that disrupted embodiment is not merely a restatement of body dissatisfaction but a distinct experiential phenomenon with its own clinical relevance.

The group comparisons were equally striking. In four analyses of covariance, controlling for age and body mass index, the women who self-identified as experiencing anorexia nervosa reported significantly higher levels of disrupted embodiment than the undergraduate women. They experienced their bodies more as a hardship, more as a threat and more as separate from their selves. These findings map directly onto the phenomenological account under investigation, indicating that the experiences philosophers have described from first-person reports and theoretical reflection are empirically detectable and measurably elevated in the population the theory was written about.

One interesting wrinkle emerged from the psychometric analyses. Bifactor analyses, combined with the consistency of the subscale-specific results, indicated that the DES may be best conceptualized as a unidimensional scale. In practical terms, this suggests that while the three dimensions of hardship, threat and separateness are theoretically distinguishable, the scale in practice measures a single underlying construct of disrupted embodiment. This has implications for future research, as it simplifies scoring and interpretation while preserving the instrument’s ability to capture the phenomenologically grounded experiences it was designed to measure. The researchers note that the one exception among their regression results does not undermine the overall pattern of support.

The implications of the study reach beyond measurement. If anorexia nervosa involves a fundamentally disrupted relationship to one’s own body, then treatments focused solely on changing beliefs about weight and shape may be addressing only part of the problem. Phenomenological accounts suggest that recovery may require restoring a lived, comfortable sense of embodiment, not simply correcting cognitive distortions. The researchers acknowledge the limitations inherent in their design: the data were cross-sectional, so the studies cannot establish whether disrupted embodiment is a cause, a correlate or a consequence of anorexia, and one participant group was defined by self-identification rather than clinical diagnosis. The samples also consisted of women, leaving open questions about how the construct applies more broadly.

Nevertheless, the work stands as a rare and successful example of empirical philosophy in action, demonstrating that careful phenomenological description can be operationalized, measured and validated, and that philosophy of mind and psychiatric science can inform one another productively. The study was funded jointly through the Kill Family Fund and the Franco Family Institute for Liberal Arts and the Public Good at the University of Notre Dame, with approval from the university’s Human Subjects Institutional Review Board and written consent from all participants. The authors declare no competing interests, and the article is published open access. As the phenomenological turn in eating disorder research gathers pace, this study provides that movement with something it has needed: hard data showing that when people with anorexia describe their bodies as burdensome, threatening and alien, those descriptions are not poetic exaggeration but measurable features of a serious illness.

Subject of Research: Empirical testing of phenomenological accounts of disrupted bodily experience in anorexia nervosa using the Disrupted Embodiment Scale

Article Title: Disrupted embodiment: empirically assessing phenomenological accounts of anorexia nervosa

Article References: Hocking, J. E., Osler, L., & Rea, M. C. (2026). Disrupted embodiment: empirically assessing phenomenological accounts of anorexia nervosa. Journal of Eating Disorders. https://doi.org/10.1186/s40337-026-01768-7

Image Credits: AI Generated

DOI: 10.1186/s40337-026-01768-7

Keywords: anorexia nervosa, eating disorders, phenomenology, embodiment, disrupted embodiment scale, body dissatisfaction, drive for thinness, body image, psychological assessment, philosophy of mind, bifactor analysis, eating disorder symptomatology