Many tools have been developed to assess and help diagnose delirium, some of which have been designed to screen for delirium when it is suspected, others are designed to monitor delirium once diagnosed, and others which are focused on categorizing the severity of delirium.1

Reference:
1. Wilson JE, Mart MF, Cunningham C, et al. Delirium. Nat Rev Dis Primers 2020; 6 (1): 90.