4 A's Test for Delirium Screening
Check each criterion present. Two or more positive items → positive screen (common teaching threshold).
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How it works
The 4 A's combine alertness, cognitive testing (AMTS), attention testing, and acute fluctuation for a rapid delirium screen.
Limits
A screen is not a diagnosis; sensitivity/specificity depends on setting and assessor training.
Educational tool only—not for diagnosis or treatment decisions.