Impaired response inhibition scale for alcoholism (IRISA): development and psychometric properties of a new scale for abstinence-oriented treatment of alcoholism.

Background: Impaired inhibition of conditioned response plays a significant role in relapse in addictive behaviors. Although patients and their relatives frequently discuss this behavioral deficit when seeking treatment, no instrument is yet available to measure its severity. The aim of this study was to develop the Impaired Response Inhibition Scale for Alcoholism (IRISA) to assess this impairment in alcohol-dependent patients.

Methods: A preliminary version of the IRISA was administered to a group of 151 patients under treatment at our center. Exploratory factor analysis was conducted using principal component analysis. The validity and reliability of the IRISA were examined.

Results: Factor analysis and item refinement led to a definitive 16-item IRISA that accounted for 61.6% of the total variance and revealed Impaired Response Inhibition as a single factor. Psychometric properties of this version of the IRISA scale showed excellent internal consistency (Cronbach's alpha: 0.96), good test-retest reliability (intraclass correlation coefficient: 0.81), and satisfactory convergent, discriminant, and predictive validity. The IRISA has a good correlation with alcohol craving, the severity of alcoholism, and alcohol consumption during the recovery process.

Conclusions: Our initial results with the IRISA suggest that it is a reliable and valid tool to measure impairment in response inhibition to drinking behavior. The IRISA assesses a potentially important aspect of treatment process and outcome.