The Addiction Severity Index: reliability and validity in a Dutch addict population

In order to meet the need for a multidimensional diagnostic instrument in the field of drug addiction in The Netherlands, the Addiction Severity Index (ASI) has been applied to a sample of Dutch drug addicts. In this article the usefulness and psychometric characteristics of the Dutch version of the ASI are discussed. Overall, there was no evidence of a general relationship between the ASI ratings of problem severity. The severity ratings showed good concurrent validity, and subscales of selected items in each problem area of the ASI were demonstrated to have good internal consistency reliability. Regression analysis indicated that the ASI items accounted for a considerable proportion of the variance in the severity ratings, indicating a strong relationship between "subjective" rating and "objective" data. On the basis of the general concept of the ASI and the satisfactory psychometric characteristics, implementation of the instrument in The Netherlands is advocated.