Development and Validation of the Anxious Distress Assessment Scale (ADS) in Patients with Major Depressive Disorder

Objective: Anxiety symptoms frequently occur alongside mood disorders and are associated with poorer clinical outcomes, highlighting the importance of early and accurate detection. This study evaluated the diagnostic accuracy and psychometric properties of the Anxious Distress Assessment Scale (ADS), a newly developed brief self-report instrument designed to detect anxious distress. Method: The study was conducted in two phases. Phase 1 involved the development of the ADS as a five-item instrument reflecting the DSM-5-TR anxious distress criteria. In Phase 2, 105 adults diagnosed with major depressive disorder (MDD) completed the ADS alongside the Generalized Anxiety Disorder-7 (GAD-7) and the Montgomery-Åsberg Depression Rating Scale (MADRS). Psychometric evaluation included internal consistency reliability (Cronbach's α), analyses of convergent validity, and diagnostic accuracy assessment using correlation and receiver operating characteristic (ROC) analyses. Results: Anxious distress was highly prevalent, with 71% of participants meeting DSM-5-TR criteria. The ADS demonstrated strong diagnostic performance, with sensitivity of 88.0%, specificity of 90.0%, positive predictive value of 95.7%, and negative predictive value of 75.0%. ROC analysis yielded an area under the curve (AUC) of 0.97 (95% CI: 0.943-0.997), with an optimal cut-off score of ≥10. Internal consistency was excellent (Cronbach's α = 0.897). Principal component analysis supported a unidimensional structure, accounting for 71.5% of the total variance, with all items loading above 0.80. The ADS also demonstrated strong convergent validity, correlating significantly with the GAD-7 (r = 0.82) and MADRS (r = 0.68). Conclusions: The ADS demonstrates promising psychometric properties, including strong reliability, meaningful convergent validity, and excellent diagnostic accuracy. Its brief format and direct alignment with DSM-5-TR anxious distress criteria support its potential utility as a practical screening tool in clinical settings. However, these findings should be interpreted in light of the study's focus on English-speaking Malaysian adults with MDD recruited from a tertiary-care setting. Further validation across diagnostic groups, clinical contexts, and cultural and linguistic populations is warranted.