The Addiction Research Center Inventory: Standardization of scales which evaluate subjective effects of morphine,amphetamine, pentobarbital,alcohol, LSD-25, pyrahexyl and chlorpromazine

Summary The ARCI, a 550-item inventory for assessing subjective drug effects and personality characteristics, was standardized using former addict subjects on a number of drug conditions. The inventory was administered under “no-drug” and placebo, and various doses of morphine, pentobarbital, chlorpromazine, LSD-25, amphetamine, pyrahexyl, and alcohol. By means of item analysis, cross-validity and other initial comparisons, items were chosen to comprise each drug scale that discriminated the particular drug from placebo; the (no-drug)-placebo comparison also produced a tentative placebo scale. Since non-significant differences were found when scoring each of the drug scales separately on the nodrug and placebo conditions, these data were combined for standardizing all scales. Validity generalization, dose-effect, and retest studies showed that the drug scales possessed a high degree of validity and reliability. In contrast, the placebo scale lost discrimination entirely in the validity generalization group. Because of the very considerable number of item comprising the scales, only examples were presented. Subjective effects of the various drugs were discussed in terms of specific and general, non-specific actions and patterns of these alterations.