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An item-response theory analysis of DSM-IV alcohol-use disorder criteria and "binge" drinking in undergraduates.

OBJECTIVE
This is the first study to examine the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), criteria for alcohol-use disorders and heavy episodic (or "binge") drinking in a college sample using item-response theory (IRT) analysis. IRT facilitates assessment of the severity of the criteria, their ability to distinguish between those at greatest and lowest risk, and the value of adding a "binge" drinking criterion.


METHOD
In a sample of undergraduate drinkers (n = 353), we conducted factor analyses to determine whether the criteria best fit a one- or two-factor structure. We then conducted IRT analyses to obtain item-characteristic curves indicating the probability of endorsing a criterion at increasing levels of alcohol-use-disorder risk. These analyses were first conducted including current (i.e., past-year) DSM-IV alcohol-use-disorder criteria only and then rerun adding weekly "binge" drinking.


RESULTS
A single-factor model of the DSM-IV criteria did not differ significantly from a two-factor model. After including "binge" drinking, two factors fit the data slightly better than one factor but with a dominant single factor. Withdrawal was the most severe criterion, whereas tolerance and "larger/longer" were the least severe. Time spent drinking and a combined social/legal difficulties criterion had the best ability to discriminate those at greatest and lowest risk for an alcohol-use disorder. "Binge" drinking showed both low discrimination and low severity.


CONCLUSIONS
To our knowledge, this is the first study to examine DSM-IV criteria in an undergraduate sample using IRT. In this sample, abuse and dependence were intermixed on a continuum of severity, and "binge" drinking was in the least severe region.