The Italian version of the Obsessive-Compulsive Drinking Scale: validation, comparison with the other versions, and difference between type 1- and type 2-like alcoholics.

The Obsessive-Compulsive Drinking Scale (OCDS) is a quick and reliable self-rating instrument for alcohol craving. Translated and validated versions are available and all of them have confirmed the utility of the scale in clinical situations. The purpose of this study was to translate and validate the Italian version of the OCDS, to assess its psychometric properties, to compare it with the other versions, and to search for possible differences between subgroups distinguished according to socio-demographic and clinical variables. The OCDS and a visual analogue scale (VAS) for alcohol craving were given to 103 Italian-speaking alcohol-dependent patients, who were assessed for their typology of alcoholism according to Cloninger's criteria. The reliability, the correlations between the variables and the influence of other factors were measured. Principal component analysis was performed to detect underlying dimensionality of the scale. The construct validity of the total scale and the subscales, as tested with Cronbach alpha analysis, was good. The r-values between total (TOT) and obsessive (OB) and compulsive (CP) subscales were comparable with those obtained in the other European studies. None of the socio-demographic parameters, nor the majority of the clinical factors significantly influenced the OCDS scores; however, there was a significant difference in total and subscale scores between Cloninger's "type 1-like" and "type 2-like" alcoholics, with the former having lower scores than the latter ones, whereas the VAS was not able to discriminate them. Principal component analysis of the 14 OCDS items showed that the scale is better described by a three-factor solution. The Italian version of the OCDS exhibited good reliability and construct validity, confirmed its psychometric properties, showed higher scores than in other studies, showed CP consistently higher than OB score, confirmed the validity of the French method for score calculation and was able to discriminate Cloninger's "type 1-like" and "type 2-like" alcoholics.