Greek Validation Confirms Five-Factor Stress Scale for Breast Cancer Patients

A breast cancer diagnosis is rarely a single moment of crisis. For most women, it sets off a cascade of stressors that unfold across years of screening, surgery, chemotherapy, hormonal therapy and follow-up appointments, touching everything from body image and intimate relationships to finances, family roles and fears about the future. Clinicians and researchers have long recognized that this burden is multidimensional, yet measuring it accurately has depended on having assessment tools that are both scientifically rigorous and linguistically and culturally appropriate. A new study from psychologists at Panteion University of Social and Political Sciences in Athens, published in BMC Psychology, addresses exactly that gap for Greece, one of the many Southern European countries where cancer-specific stress measures validated in the local language have been conspicuously absent.

The research, led by Katerina Chotzoglou with co-authors Georgia Raftopoulou and Eirini Karakasidou, set out to evaluate the psychometric properties of a Greek translation of the Stressors in Breast Cancer Scale, commonly abbreviated as the SBCS. The instrument is a 24-item self-report questionnaire designed to capture five distinct domains of stress experienced by women with breast cancer: concerns about appearance and sexuality, worries about health and daily life, strains on interpersonal relationships, frustrations with the healthcare system, and anxieties about the future. The team’s central question was whether this five-factor architecture, established in the original development of the scale, would hold up when the instrument was administered in Greek to women navigating the disease within the Greek healthcare and cultural context.

The study employed a cross-sectional design, recruiting 216 Greek women who had received a breast cancer diagnosis. Recruitment was facilitated by the Panhellenic Association of Women with Breast Cancer and the 2nd Breast Clinic of IASO Hospital in Athens, partnerships the authors explicitly acknowledge as essential to reaching patients across the care continuum. The research was approved by the Research Ethics Committee of Panteion University, registered under number 52/10-03-2025, and all participants provided informed consent. The authors declare no competing interests and note that the work received no external funding from public, commercial or not-for-profit sources, a detail that underscores how much of psycho-oncology research still depends on institutional commitment rather than dedicated grant programs.

At the heart of the study lies a battery of statistical techniques that psychometricians use to interrogate whether a questionnaire actually measures what it claims to measure, and whether its internal structure is coherent. The researchers first applied Exploratory Factor Analysis, a family of methods that examines patterns of correlation among items to identify underlying latent dimensions without imposing a predetermined structure. They then turned to Confirmatory Factor Analysis, a more stringent approach in which a hypothesized factor structure is specified in advance and tested against the observed data using structural equation modeling. The fact that both exploratory and confirmatory approaches were used gives the findings additional weight, because agreement between the two provides stronger evidence than either alone that the five-domain architecture is not a statistical artifact.

The results were encouraging. The confirmatory analysis supported the original five-factor structure of the Greek version of the scale, with fit indices falling within acceptable ranges: the Comparative Fit Index reached .956 and the Tucker-Lewis Index .951, both comfortably above the conventional .95 threshold that signals good model fit. The Root Mean Square Error of Approximation was .080 and the Standardized Root Mean Residual was .063, values that sit within the range generally regarded as acceptable for psychological instruments, particularly in applied clinical research where samples are rarely enormous. In practical terms, these numbers mean that the 24 items clustered into the five expected domains in the Greek sample much as they do in the scale’s original form, suggesting that the psychological content of the stressor domains translates meaningfully across languages and healthcare settings.

Reliability, the second pillar of the validation, was assessed using two complementary coefficients. Cronbach’s alpha, the classic measure of internal consistency, estimates how closely a set of items taps a single underlying construct, while McDonald’s omega offers a related estimate grounded in factor-analytic assumptions and is often considered more robust when items differ in how strongly they load on their factor. The Greek version of the scale achieved an alpha of .94, a figure indicating very high internal consistency across the full instrument. For clinicians, that translates into a measure on which scores are stable and interpretable, reducing the measurement noise that can obscure genuine differences between patients or changes within a patient over time.

Validity evidence extended beyond the internal structure. The researchers examined convergent validity by testing whether scores on the Greek Stressors in Breast Cancer Scale correlated, as theory predicts, with other established measures of psychological distress. The scale showed strong positive correlations with both perceived stress and anxiety, exactly the pattern one would expect if the instrument is genuinely capturing cancer-related stress rather than something unrelated. Discriminant validity was evaluated through a different logic: the researchers compared the square roots of the Average Variance Extracted for each factor with the correlations among the factors, a standard technique for confirming that the five domains, while related, remain empirically distinguishable from one another rather than collapsing into a single undifferentiated distress score.

Why does this matter beyond the statistics? Generic stress questionnaires exist in Greek, but they were not designed to probe the specific terrain of a cancer experience: the grief over a changed body, the strain on a marriage, the bewilderment of navigating hospital bureaucracy, the dread of recurrence. A validated cancer-specific measure allows oncology teams, psychologists and researchers to identify which of these domains is most burdensome for an individual patient or a patient group, and to tailor psychosocial interventions accordingly. It also enables Greek data to be compared with international studies using the same instrument, opening the door to cross-cultural research on how the subjective burden of breast cancer varies across healthcare systems and societies. In a country where psycho-oncology services remain unevenly distributed, a reliable, brief, structured assessment tool is a practical prerequisite for evidence-based supportive care.

The study’s authors are careful about scope, as good psychometric work should be. The sample of 216 women, while adequate for the factor-analytic methods employed, is a cross-sectional snapshot rather than a longitudinal record, so the findings speak to the structure and reliability of the scale at a single point in time. Further research could examine test-retest reliability, sensitivity to change over the disease trajectory, and performance in clinical subgroups. The article itself was published as an open-access paper on 8 October 2026 under a Creative Commons license, with a note that the version shared early is citable and carries a permanent DOI while remaining subject to final editorial edits before the Version of Record replaces it.

Even with those caveats, the contribution is concrete. Greece now has a validated, five-domain, cancer-specific stress instrument with strong internal consistency and convergent validity evidence, developed and tested with the participation of Greek women with breast cancer and their advocacy organizations. For the growing field of patient-reported outcomes, in which the subjective experience of illness is treated as data as legitimate as tumor markers and imaging, the study is a reminder that measurement science is the quiet infrastructure of personalized cancer care. A questionnaire that reliably distinguishes worries about appearance from fears about the future, or relational strain from institutional frustration, gives clinicians a map of where a patient’s suffering actually lies, and that map is often the first step toward effective help.

Subject of Research: Psychometric validation of a breast cancer-specific stress assessment scale in Greek patients

Article Title: Psychometric validation of the Stressors in Breast Cancer Scale in Greece: evidence for a five-factor structure

Article References: Chotzoglou, K., Raftopoulou, G., & Karakasidou, E. (2026). Psychometric validation of the Stressors in Breast Cancer Scale in Greece: evidence for a five-factor structure. BMC Psychology. https://doi.org/10.1186/s40359-026-05623-x

Image Credits: AI Generated

DOI: 10.1186/s40359-026-05623-x

Keywords: psychometrics, breast cancer, stress assessment, psycho-oncology, scale validation, factor analysis, patient-reported outcomes, Greece, psychological testing, quality of life, anxiety, BMC Psychology