4AT – 2 minute delirium detection validated in 30+ studies

Evidence-based bedside tool for rapid delirium screening across acute, community, and peri-operative settings.

  • ~2 min administration time

  • No training required: designed for immediate use by nurses, doctors, and AHPs

  • Extensive evidence: 33 diagnostic‑accuracy studies (>6000 pts)

  • High sensitivity & specificity

  • Globally adopted: translated into >20 languages & included in national guidelines

  • Completely free: instant access, no registration required

  • Free EHR integration: ready for systems like EPIC with no licensing required

  • Built-in cognitive testing: identifies possible cognitive impairment as well as delirium in a single assessment - supporting Age-Friendly Hospital ‘Mentation’ workflows and CMS 4Ms implementation


"Balancing the evidence for accuracy and cost effectiveness with the practicality of implementing the tests, the committee agreed that the 4AT was the best option for most settings.

It is among the most accurate of the tools reviewed, quick and simple to use, and has a broader range of evidence to support it."

- UK NICE Guideline on Delirium, 2023

A resource to share

Help families understand delirium

Delirium Support is a free, plain-English website about delirium (sudden confusion) for families and carers. Share it during or after conversations about suspected or diagnosed delirium. It explains what delirium is, what families can do, and what recovery may be like, with one-page guides to print or download.

Visit Delirium Support

deliriumsupport.com · Free to use and share

<3 min video walkthrough of 4AT: see how easy it is!


Delirium (Acute Confusion): A Family Guide to Sudden Changes in Thinking and Memory

A detailed guide for families and caregivers - coming soon. By Professor Alasdair MacLullich (4AT author) and Dr Sharmella Summan.


More details