Confusion Assessment Method (CAM)

Inouye SK, van Dyck CH, Alessi CA, Balkin S, Siegal AP, Horwitz RI. Clarifying confusion: the confusion assessment method. A new method for detection of delirium. Derived and validated the four-feature diagnostic algorithm used here against a psychiatrist’s DSM-III-R diagnosis (sensitivity 94–100%, specificity 90–95% across two sites).

CAM is a diagnostic algorithm, not a screen you can use untrained — accurate use assumes the rater has assessed attention and the other features with a brief bedside cognitive test (e.g. counting backward from 20, reciting the months backward) and knows the patient’s cognitive baseline. It does not grade delirium severity; a positive CAM prompts a search for and treatment of the underlying cause(s).