Table 4 offers information that may help to explain why severity weighting of criteria did not result in a severity scale more strongly associated with outcome measures than the simple count of criteria. Using average daily volume of consumption as an example, Table 4 shows that some of the criteria are operationalized by symptoms that are widely divergent in terms of their apparent severity. For the criterion of tolerance, for example, the average daily volume of ethanol intake among individuals who endorsed the symptom item of drinking the equivalent of a fifth of liquor in a day was twice as great as that among individuals endorsing the symptom item reflecting a decreasing effect of the usual number of drinks, 5.20 versus 2.55 ounces. The variation across symptom items was even more striking in the case of withdrawal; however, it is difficult to interpret the severity associated with any single symptom item because two positive symptoms are required to satisfy the DSM-IV conceptualization of withdrawal as a syndrome. Other criteria marked by a fairly wide range of symptom severity include impaired
