ABSTRACT
Objective:To test the reliability of the short version of the depression-anxiety-stress scale (DASS-21) in adolescents through generalizability theory.Methods:Total of 458 adolescents from three middle schools in Guizhou and Sichuan province were surveyed with the DASS-21 from November to December 2021.Based on multivariate generalization theory(MGT), the generalization coefficients, reliability indexes and variance contribution ratios were calculated.mGENOVA 2.1 was used for data analysis.Results:The generalizability coefficient and reliability index for the total scale of DASS-21 were 0.927 and 0.922, respectively.The generalizability coefficients of depression, anxiety and stress subscales were 0.808-0.840, and the dependability indexes were 0.789-0.832.The contribution ratios of depression, anxiety and stress subscales to the general score were 33.20%, 33.94% and 32.86%, respectively.The stress subscale (34.95%) contributed the most to the relative error variance, and the anxiety subscale (36.98%) contributed the most to the absolute error variance.Conclusion:The DASS-21 has excellent test reliability in adolescents, and it can be used both as the norm-referenced test and the criterion-referenced test in the actual assessment of negative emotions in adolescents.