This analysis also illustrated the limitations of a severity scale based solely on a count of criteria endorsed, regardless of whether weighted or unweighted. The severity of some of the criteria was highly dependent on the symptom items with which they were endorsed. This was particularly the case for the physiological dependence criteria of tolerance and withdrawal, but also true for impaired control and to a lesser degree for hazardous use and time spent drinking. The range of severity indicated by variation in mean volume of intake for individuals endorsing various symptoms parallels IRT-based severity parameters for the symptoms as reported in an earlier analysis (Kahler et al., 2006), and it indicates that some criteria have the potential for representing a far greater level of AUD severity than they do for the majority of individuals endorsing those criteria. It also illustrates that possibly redundant criteria, i.e., those that represent very similar levels of severity, could be better discriminated by choosing operationalizations that led to more dispersion along the latent trait of AUD severity.
