Should tolerance and withdrawal be required for substance dependence disorders?

Despite the historical importance of tolerance and withdrawal in the substance abuse nomenclature, empirical evaluations of tolerance and withdrawal relative to other, non-physical, dependence criteria have been infrequent. Based on data from 521 subjects from a newly completed survey evaluating proposed options for DSM-IV substance use disorders, we found, first, across classes of drugs, requiring tolerance or withdrawal had little effect on rates of dependence, as most subjects who met dependence criteria for each drug class also reported tolerance. Second, tolerance and withdrawal did not emerge as superior to the other dependence criteria on several indicators of concurrent and predictive validity, including severity.