Using a bifactor exploratory structural equation modeling framework to examine the factor structure of the Depression Anxiety and Stress Scales-21

This study proposed an improved representation of the DASS-21 factor structure developed by Lovibond and Lovibond in Behaviour Research and Therapy, 33, 335-342 (1995) using bifactor exploratory structural equation modeling (bifactor ESEM). This research was conducted by reference to 521 Turkish adults (45.3% females; M-age = 27.86, SD = 8.23). The bifactor ESEM findings indicated a strong general factor of negative affect underlying responses to all DASS-21 items but also that despite the presence of three specific factors (depression, anxiety, and stress), the depression subscale explained a high degree of variance and could be considered to constitute a specific factor. The results obtained from this study show that there is a common factor associated with DASS-21 scales, the total score of DASS-21 can be identified as a measure of general negative affect, and the bifactor ESEM structure of DASS-21 ensures measurement invariance across genders.