Evaluation of the psychometric properties and convergent validity of the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) questionnaire in Brazilian young adults

This cross-sectional study aims to evaluate the psychometric properties and the convergent validity of the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST). Confirmatory factor analysis (CFA) and linear regression adjusted for confounding factors were performed to obtain the adjusted beta value (βadj) for sleep quality (Pittsburgh Sleep Quality Index), burnout (Copenhagen Burnout Inventory), and depressive symptoms (Patient Health Questionnaire-9). The study population consisted of 3187 young adult university students. The CFA indicated adequate fits for the one- and two-factor structure of the ASSIST, with better indices for the two-factor model. Convergent validity results confirmed the best fit of the one-factor model (version 3.1), in which individuals classified as “suggestive of dependence” showed a greater effect on worse sleep quality (βadj 2.16, 95% confidence interval (CI) 1.48–2.84), burnout (βadj 12.25, 95% CI 8.43–16.06), and depressive symptoms (βadj 6.69, 95% CI 5.37–8.00). The results and the literature review indicated that the one-factor presents an adequate factor structure and better convergent validity.