Psychometric Properties of the Sixth Version of the Addiction Severity Index (ASI-6) in Brazil

Background: There are few research tools in Brazil to assess more broadly the alcohol and other drug related problems.

Objective: To test the psychometric properties of ASI in its sixth version (ASI-6).

Methods: A multicenter cross-sectional study was conducted in four Brazilian state capitals. Four research centers interviewed 150 adult inpatients or outpatients, and one research center interviewed 140 patients. A total of 740 substance abusers were selected. Training and supervision of interviewers were performed to assure the quality of dada collected.

Results: Most areas of the ASI showed good reliability between the instrument and the interviewers, with no statistically significant differences between the ASI-6 Summary Scores for Recent Functioning (SS-Rs) of both interviews. Cronbach's alpha for ASI-6 subscales ranged from 0.64 to 0.95. Correlations between the ASI-6 Alcohol and Drug scores and the concurrent instrument (ASSIST) were high (0.72 and 0.89, respectively). There was a significant negative correlation between the scores in psychiatric, medical and drug areas and the scores of WHOQOL.

Conclusion: Analysis of the psychometric properties of ASI-6 both in outpatients and inpatients in Brazil indicate a good reliability and validity of this instrument for the Brazilian culture. The development of this instrument in Brazil is an important advancement, which will certainly have implications for the prevention, clinical research, and social rehabilitation fields.