Psychometric and discriminative properties of the Teen Addiction Severity Index (Brazilian Portuguese version).

In this study we evaluated the internal consistency of the Brazilian Portuguese version of Teen Addiction Severity Index (T-ASI) and validated its "substance use" area. Evaluating 100 psychoactive substance abusers/dependent adolescents (SUD) and 108 adolescents without such diagnosis (NON-SUD), we found good correlations between the classification by the Composite International Diagnostic Interview (CIDI, used as "gold standard") and the severity (r = 0.73) and composite (r = 0.72) scores of the T-ASI. The area under the ROC curve was 0.88, showing a satisfactory correct classification rate. The internal consistency, evaluated by Cronbach's alpha coefficients, was considered good regarding the substance use (0.89), legal (0.81), and psychiatric (0.80) areas of the T-ASI. The Brazilian Portuguese version of T-ASI presented good internal consistency and a valid substance use area. A comparison between the groups regarding the answers to each question in all the areas was conducted in order to identify which questions in the T-ASI discriminate SUD from NON-SUD adolescents, to have a basis for the proposal of a shorter version of the instrument.