Validation of the Behavioral Activation for Depression Scale in Individuals With Substance Use Disorders

This cross-sectional observational study evaluates the psychometric properties, structural validity, item response characteristics, and concurrent criterion validity of the Behavioral Activation for Depression Scale (BADS) in adults receiving clinical treatment for substance use disorders (SUD). The study examines the scale's dimensional structure, reliability, and association with environmental reward (Environmental Reward Observation Scale, EROS) in a primary clinical cohort of 289 participants. Concurrent and discriminant validity analyses with additional clinical measures (assessing borderline symptom severity, impulsivity, anxiety, and anger expression) were evaluated in a verified sequential subcohort of 59 participants with fully confirmed individual-level linkage across multi-scale administration sheets. This retrospective study record documents the completed psychometric evaluation conducted within a specialized residential therapeutic community.

Inclusion Criteria: * Adults aged 18 to 68 years. * Primary clinical diagnosis of Substance Use Disorder (evaluated in accordance with DSM-5 criteria) currently receiving residential or intensive clinical treatment in a therapeutic community setting. * Literacy and fluency in Spanish sufficient to complete self-report instruments. * Provision of voluntary written informed consent. * Completion of the Behavioral Activation for Depression Scale (BADS). Exclusion Criteria: * Severe cognitive impairment, active psychosis, or acute neurological conditions precluding accurate self-reporting. * Active substance intoxication or acute withdrawal symptoms at the time of testing that interfere with questionnaire completion. * Substantial missing data preventing psychometric modeling (participants with at least 75% item completion on the primary instrument were retained for categorical estimation under pairwise/FIML algorithms).