Further validating of the Depression Anxiety Stress Scales-21 (Dass-21) in Chinese adolescents: factor structure and measurement invariance.

backgroundPrior studies of the Depression Anxiety Stress Scales-21 (DASS-21) have validated its first-order three-factor structure (e.g., depression, anxiety, and stress) in Chinese students and/or adult populations. This study aimed to further examine alternative factor models (e.g., higher-order structure model, bifactor model), and measurement invariance (e.g., across genders, and across grade levels) of the DASS-21 among Chinese adolescents.

methodsTwo samples were collected by the convenience sampling. More specifically, the Sample 1 (n1 = 472, 50.2% boy, Mage=14.91) was collected from three middle schools in Guizhou and Sichuan Province; the Sample 2 (n2 = 564, 44.5% boy, Mage=13.62) was collected from three middle schools in Guizhou Province. The Depression Anxiety Stress Scales-21 (DASS-21), and other criterion measures (e.g., MMHI-A, MMHI-AS, GAD-7, PHO-9, and WHO-5) were completed by the adolescents. The confirmatory factor analysis (CFA), multi-group CFA, internal consistency, and zero-order correlation were used to evaluate the results.

resultsThe CFA supported a three-factor bifactor structure model for the DASS-21, and multi-group CFAs further demonstrated the bifactor model of DASS-21 scores exhibited scalar invariance across gender (boys and girls) and grade levels (junior high and high school students). Additionally, the DASS-21 scores displayed satisfactory internal consistency, as indicated by alpha and omega coefficients. Finally, the criterion validity was established based on the expected relationships between the DASS-21 scores and external variables (depression, anxiety, academic stress, and well-being).

conclusionThe DASS-21 is an effective tool designed for young people, used to measure common mental health statuses—such as anxiety, depression, and stress—and the general distress factor among Chinese adolescents.