Predictive accuracy of the 8- and 12-item versions of the DASS-21 in measuring depression, anxiety and stress in Brazilian university students

OBJECTIVES: To evaluate the predictive value of the DASS-8 and DASS-12 scales, derived from the full DASS-21, in assessing mental health among Brazilian university students, highlighting the innovation of validating ultra-brief instruments specifically designed to maintain high psychometric performance while enabling rapid, large-scale mental health screening in resource-constrained academic settings. STUDY DESIGN: Multicenter cross-sectional study. METHODS: Study carried out with students at eight public universities in Brazil. Data was collected through a self-completed online questionnaire. Symptoms of depression, anxiety, and stress were assessed using the DASS-21. The concurrent validity of the reduced versions of the DASS-12 and DASS-8 was determined using ROC curve analyses and sensitivity, specificity, and accuracy tests, using the DASS-21 as a reference standard. Regression models evaluated the invariance between sociodemographic and health factors with mental health outcomes in the DASS-21; DASS-12 and DASS-8. RESULTS: A total of 8650 study participants were evaluated, the majority were female (65.7 %) and aged between 18 and 22 (54.2 %). The DASS-21; 12 and 8 had excellent internal consistency (α and ω ≥ 0.91). ROC curve analysis yielded AUC values indicating strong predictive validity, with the DASS-12 reported 0.93, 0.91, and 0.90, while the DASS-8 showed AUCs of 0.92, 0.90, and 0.89 for depression, anxiety, and stress, respectively. Sensitivity ranged from 94 % to 97 % for depression, 84 %-94 % for anxiety, and 87 %-96 % for stress, with high specificity and accuracy across all subscales (>90 %). Factors associated with symptoms across the three subscales by DASS-21 were similar to those identified by DASS-12 and DASS-8. CONCLUSION: The DASS-8 and DASS-12 scales showed reliability and effectiveness in screening for symptoms of depression, anxiety, and stress in Brazilian university students.