4AT (Rapid Clinical Test for Delirium)

A ultra-brief screener for delirium and cognitive impairment


The 4AT was originally designed in 2011 by Prof Alasdair MacLullich (Edinburgh Delirium Research Group, University of Edinburgh, Scotland), and Dr Tracy Ryan and Dr Helen Cash (NHS Lothian, Scotland) to screen for delirium. The 4AT is an easy and quick tool for delirium detection designed for use in clinical practice. The 4AT takes less than 2 minutes, suitable for use in normal clinical practice, no special training is required, and includes brief cognitive tests. The 4AT has been shown to have a pooled sensitivity of 88% and a pooled specificity of 88%. The 4AT is not designed for repeated daily monitoring or for new onset delirium.


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1. Alertness

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This includes patients who may be markedly drowsy (eg. difficult to rouse and/or obviously sleepy during assessment) or agitated/hyperactive. Observe the patient. If asleep, attempt to wake with speech or gentle touch on shoulder. Ask the patient to state their name and address to assist rating.

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