Validation and Reliability of the Depression Anxiety Stress Scale for Youth (DASS-Y) Indonesian Version.

Background: The Depression Anxiety Stress Scale for Youth (DASS-Y) is a psychometric tool designed to assess internalizing problems, including depression, anxiety, and stress in adolescents. This study evaluated the validity and reliability of the Indonesian version of the DASS-Y. Methods: Using a mixed-methods approach with an exploratory sequential design, the DASS-Y was translated into Bahasa Indonesia through forward-backward translation and administered to 31 adolescents for the cognitive debriefing. The Rasch model was applied to assess psychometric properties in 355 adolescents. Results: The Indonesian version of the DASS-Y indicated good-to-excellent reliability for the total scale (Cronbach's α = 0.94, item reliability = 0.98, person reliability = 0.84) and robust construct validity (explained variance = 50.1%, unexplained variance = 6.4%). No misfitting items were identified (infit = 0.78-1.41, outfit = 0.61-1.96, point-measure correlation = 0.47-0.72). Differential item functioning (DIF) analysis revealed minimal bias across demographic factors. Conclusion: The Indonesian DASS-Y is a valid and reliable instrument for assessing internalizing problems in Indonesian adolescents aged 10-18 years.