Validation of the Pashto version of the 21-item Depression, Anxiety, and Stress Scale (DASS-21) among Afghans

Background The 21-item depression, anxiety, and stress scale (DASS-21) is an important and useful self-administered screening instrument designed to measure depression, anxiety, and stress. Currently, there is no published study using the Pashto version of the DASS-21 scale. Hence, the main objective of this research was to study the psychometric properties of the Pashto version of the DASS-21 among Pashto-speaking adult Afghans living in Kandahar and Helmand provinces of Afghanistan. Methods This cross-sectional study was conducted between January and March 2024 among 619 adults using convenience sampling technique. The mean age of the study participants was 37.4 years, ranging from 18–100 years. Internal consistency was evaluated using Cronbach’s alpha. Test-retest reliability was assessed via the Intraclass Correlation Coefficient (ICC). Inter-rater agreement for the scale's test-retest reliability was examined using Cohen's kappa. Convergent validity was assessed through Pearson correlation analyses, comparing DASS-21 subscales (depression, anxiety, and stress) with the GHQ-28 (depression and anxiety subscales) and CES-D 20 (total and subscale scores). Results The Cronbach’s alpha for the 21 items was 0.942, which indicates excellent internal consistency. The total score revealed a commendable ICC of 0.902, reflecting a consistently reliable measure encompassing all subscales. The F-test was statistically significant across all dimensions, which further supported the scale's reliability, highlighting the measurement instrument's stability over the test-retest intervals. There were statistically significant positive correlations between the DASS-21 Depression subscale and both the CES-D-20 (r = 0.702) and the GHQ-28 Depression (r = 0.755). The DASS-21 Anxiety subscale showed strong positive correlations with the CES-D-20 (r = 0.622) and the GHQ-28 Anxiety (r = .659). The DASS-21 Stress subscale also exhibited comparable positive associations with the CES-D-20 (r = 0.700) and the GHQ-28 Anxiety (r = 0.663). Also, the DASS-21 Depression subscale demonstrated a strong positive correlation with both the DASS-21 Anxiety (r = 0.780) and the DASS-21 Stress (r = 0.806) subscales. Meanwhile, all subscales, along with the overall DASS-21, exhibited favorable fit indices, thereby supporting the proposed factor structure. Conclusion The Pashto version of DASS-21 is proven to be a reliable and valid instrument to assess the magnitude of depression, anxiety, and stress among the Pashto-speaking Afghan adult population in Kandahar and Helmand provinces. The Pashto version of the DASS-21 will allow Afghan clinicians and researchers to screen common mental health disorders among the Pashto-speaking Afghan population.