WHAT IS THE 4AT?
The 4AT is a rapid clinical instrument for delirium detection.
It is a short and practical tool designed for use in busy areas where assessment for delirium is needed.
The 4AT is among the most widely-used clinical tests for delirium internationally.
The 4AT is free to download and use.
Key features of the 4AT:
♦ takes <2 minutes
♦ suitable for use in normal clinical practice
♦ practical and simple
♦ no special training is required
♦ allows assessment of ‘untestable’ patients (that is, patients with severe drowsiness or agitation)
♦ includes brief cognitive tests
The 4AT is designed to be used by any health professional at first contact with the patient, and at other times when delirium is suspected.
It incorporates the Months Backwards test and the Abbreviated Mental Test - 4 (AMT4), which are short tests for cognitive impairment. This provides basic cognitive testing, aimed at detecting moderate-severe cognitive impairment, alongside assessment for delirium. See the guidelines on the 4AT form for more information.
The 4AT is supported by several validation studies.
Note that the 4AT is not designed for repeated daily monitoring for new onset delirium (because of practice effects with the Months Backwards task). Altered level of arousal (Item 1), and change or fluctuation (Item 4) can readily be used daily or even more frequently, along with general clinical judgement and/or use of tools specifically designed for ongoing monitoring of delirium.
REFERENCES (INCLUDING VALIDATION STUDIES)
Disclaimer: responsibility for the interpretation of scores and any actions rests with the clinical team using the 4AT. As per accepted clinical practice, a diagnosis of delirium should always be made following clinical assessment by suitably qualified staff.
Website: Alasdair MacLullich