Rating the severity of delirium: The delirium assessment scale

Explicit operational definitions of the DSM‐3 criteria for delirium have recently been published. In this study, the reliability of the Delirium Assessment Scale (DAS), which uses the operationalized criteria to determine the severity of delirium symptoms, was examined. Three independent assessors examined four groups of patients —patients with delirium, patients with delirium and dementia, patients with dementia alone and patients without cognitive impairment. Sensitivity (83–88%) and specificity (79–88%) of the operationalized definitions for the diagnosis of delirium were high. Satisfactory interrater agreement was obtained for all individual symptoms of the DAS (kappa = 0.66–0.99). These results suggest that the DAS may be suitable for monitoring the severity of delirium; prospective studies are required to confirm this hypothesis.