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

Abstract

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; Mage = 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.