Validation of the 4AT, a new instrument for rapid delirium screening: a study in 234 hospitalised older people

TLDR: The 4AT is a sensitive and specific method of screening for delirium in hospitalised older people and its brevity and simplicity support its use in routine clinical practice.

Abstract: Objective: to evaluate the performance of the 4 ‘A’s Test (4AT) in screening for delirium in older patients The 4AT is a new test for rapid screening of delirium in routine clinical practice Design: prospective study of consecutively admitted elderly patients with independent 4AT and reference standard assessments Setting: an acute geriatrics ward and a department of rehabilitation Participants: two hundred and thirty-six patients (aged ≥70 years) consecutively admitted over a period of 4 months Measurements: in each centre, the 4AT was administered by a geriatrician to eligible patients within 24 h of admission Reference standard delirium diagnosis (DSM-IV-TR criteria) was obtained within 30 min by a different geriatrician who was blind to the 4AT score The presence of dementia was assessed using the Alzheimer's Questionnaire and the informant section of the Clinical Dementia Rating scale The main outcome measure was the accuracy of the 4AT in diagnosing delirium Results: patients were 839 ± 61 years old, and the majority were women (64%) Delirium was detected in 123% (n = 29), dementia in 312% (n = 74) and a combination of both in 72% (n = 17) The 4AT had a sensitivity of 897% and specificity 841% for delirium The areas under the receiver operating characteristic curves for delirium diagnosis were 093 in the whole population, 092 in patients without dementia and 089 in patients with dementia Conclusions: the 4AT is a sensitive and specific method of screening for delirium in hospitalised older people Its brevity and simplicity support its use in routine clinical practice