BACKGROUND the 14-item Obsessive Compulsive Drinking Scale (OCDS) is a quick and reliable self-rating instrument that provides a total and two subscale scores that measure some cognitive aspects of alcohol "craving". This study validated further its utility as an alcoholism severity and treatment outcome instrument. METHODS Alcoholism severity and analogue craving scales were administered at baseline, and the OCDS was given at baseline and weekly to 41 alcohol-dependent individuals who participated in a 12-week pharmacologic and cognitive-behavioral treatment trial. Repeated-measures analysis of variance was used to examine group differences in the OCDS scores of those individuals who remained abstinent or drank during the trial. RESULTS At baseline, the OCDS was correlated with the alcohol composite score of the addiction severity index (r=.48), the alcohol dependence scale (r=.42), the analogue craving measures (range r=.40 to .57), and prestudy alcohol consumption (r=.60). Most importantly the OCDS total and subscale scores were significantly different between individuals who had relapse drinking, who had "slip" drinking, and who remained abstinent, with relapsers showing the highest scores. CONCLUSIONS The OCDS scores appear to be sensitive to alcoholism severity and change during abstinence and relapse drinking. Since the shared variance with analogue craving measures is only about 20% to 30%, it appears to be measuring a largely independent dimension of alcohol dependence. Its ease of use (5 minutes per self-rating), reliability, validity, and analytic capabilities support its utility as a tool to measure severity and improvement during alcoholism treatment trials.