Why use it

Fastest validated cognitive screening tool for acute settings. Can be completed in under 60 seconds. Validated for delirium screening in emergency departments, medical wards, and community settings. Comparable sensitivity to longer tools for detecting significant impairment in elderly patients.

About

The Abbreviated Mental Test 4 (AMT-4) is an ultra-brief 4-item cognitive screening tool validated for detecting cognitive impairment and delirium in elderly patients in acute settings. It is derived from the original 10-item Abbreviated Mental Test (AMT-10) developed by Hodkinson. The AMT-4 tests four key orientation items: age, date of birth, place, and year. A score < 4 suggests significant cognitive impairment or delirium requiring further evaluation.

When to use

Acute confusion or altered mental status in elderly patients
Delirium screening on hospital admission and serial monitoring
Quick cognitive assessment when patient tolerance is limited
Emergency department triage of elderly patients
Pre-anesthesia cognitive baseline

Formula

4 items, 1 point each: 1. Age (exact) 2. Date of birth (day and month sufficient) 3. Place (name of the location / hospital) 4. Current year Total: 0–4

Pearls & pitfalls

AMT-4 items: age, date of birth, place (name of hospital/location), and year.
Score of 3/4 or less is considered abnormal and warrants further evaluation.
The 4AT (Alertness, AMT-4, Attention, Acute change) incorporates AMT-4 and is validated for delirium screening.
AMT-4 has less ceiling effect than the MMSE in detecting delirium in patients with baseline dementia.
Sensory or language barriers may limit interpretation — document if applicable.
Always assess for reversible causes of delirium: infection, metabolic, medications, pain, urinary retention.

Next steps

AMT-4 score 4/4: Low probability of significant cognitive impairment — reassuring, but does not exclude delirium. AMT-4 score < 4: Significant concern for cognitive impairment or delirium — complete full assessment (AMT-10, MMSE, CAM, or 4AT). Investigate for reversible causes of acute confusion.

Evidence

The AMT-4 was validated in multiple UK hospital populations. The 4AT study (Bellelli et al., BMJ Open 2014) validated the AMT-4 as a component. The AMT-4 shows sensitivity ~65% and specificity ~85% for delirium when used as part of the 4AT instrument.

References

Hodkinson HM. Evaluation of a mental test score for assessment of mental impairment in the elderly. Age Ageing. 1972;1(4):233-238. — link
Bellelli G et al. Validation of the 4AT, a new instrument for rapid delirium screening: a study in 234 hospitalised older people. Age Ageing. 2014;43(4):496-502. — link

Abbreviated Mental Test 4 (AMT-4)

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