I just had a look at the brief cognitive screening tool for delirium developed by Professor Alasdair MacLullich MRCP(UK), PhD of the Edinburgh Delirium Research Group at the University of Edinburgh, Scotland. Recall Dr. MacLullich and colleagues are studying the Edinburgh Delirium Test Box (EDTB, see latest post at shortlink http://wp.me/p1glcu-UB. I found out about the 4 A’s test or the 4AT from his slide set presentation, located at the American Delirium Society (ADS) web site, which you can find in the menu above. Just click on the “2011 Conference Info”. This was presented at the inaugural conference of ADS held in Indianapolis, Indiana in June 5-7, 2011. Look for the “Alasdair MacLullich Neuropsychology Presentation”.
Anyway the test is not copyrighted and it goes like this:
Alertness: Observe the patient. If asleep, attempt to awaken with speech or gentle touch on shoulder. Ask the patient to state his full name and address.
Normal (fully alert throughout), score 0
Mild sleepiness for <10 seconds after waking, then normal, score 0
Clearly abnormal (drowsy/stupor/agitation/restlessness), score 4
AMT4 (this stands for the Abbreviated Mental Test): Ask orientation questions: Age, date of birth, place (building), year
No mistakes, score 0
1 mistake, score 1
2 or more mistakes/untestable, score 2
Attention: Ask the patient: “Please tell me the months of the year in backwards order, starting at December.” If necessary, one prompt (to assist initial understanding) of “what is the month before December?” is permitted.
No mistakes, score 0
Any mistakes/failure to complete/verbal refusal, score 1
Untestable (cannot even start), score 2
Acute change or fluctuating course: From one or more source(s) of information, e.g., rater knowledge of patient, casenotes, carers, nurses.
Evidence of acute change OR fluctuation in: alertness OR cognition arising over last 2 weeks or less and present in last 24 hours; e.g., confusion, sleepiness, agitation, restlessness, sleep disturbance, delusions, or hallucinations.
No, score 0
Yes, score 4
Score of 4 or above: possible delirium
Score of 1-3: possible cognitive impairment
Score of 0: delirium or cognitive impairment unlikely (but delirium possible if item 4 information complete)
Patients with suspected delirium and/or cognitive impairment require more detailed assessment.
The 4AT can be downloaded free (no copyright) from: http://www.the4AT.com, although good luck trying to print it from there. I couldn’t get a usable paper copy.
The 4AT could be easily implemented by nurses or doctors, although I suspect it takes a bit longer to administer than the Mini-Cog in concert with the Confusion Assessment Method (CAM) . The Acute change or fluctuating course item sounds a lot like our old friend the SQiD (Single Question in Delirium) .
1. Inouye, S. K., C. H. van Dyck, et al. (1990). “Clarifying confusion: the confusion assessment method. A new method for detection of delirium.” Ann Intern Med 113(12): 941-948.
OBJECTIVE: To develop and validate a new standardized confusion assessment method (CAM) that enables nonpsychiatric clinicians to detect delirium quickly in high-risk settings. DESIGN: Prospective validation study. SETTING: Conducted in general medicine wards and in an outpatient geriatric assessment center at Yale University (site 1) and in general medicine wards at the University of Chicago (site 2). PATIENTS: The study included 56 subjects, ranging in age from 65 to 98 years. At site 1, 10 patients with and 20 without delirium participated; at site 2, 16 patients with and 10 without delirium participated. MEASUREMENTS AND MAIN RESULTS: An expert panel developed the CAM through a consensus building process. The CAM instrument, which can be completed in less than 5 minutes, consists of nine operationalized criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R). An a priori hypothesis was established for the diagnostic value of four criteria: acute onset and fluctuating course, inattention, disorganized thinking, and altered level of consciousness. The CAM algorithm for diagnosis of delirium required the presence of both the first and the second criteria and of either the third or the fourth criterion. At both sites, the diagnoses made by the CAM were concurrently validated against the diagnoses made by psychiatrists. At sites 1 and 2 values for sensitivity were 100% and 94%, respectively; values for specificity were 95% and 90%; values for positive predictive accuracy were 91% and 94%; and values for negative predictive accuracy were 100% and 90%. The CAM algorithm had the highest predictive accuracy for all possible combinations of the nine features of delirium. The CAM was shown to have convergent agreement with four other mental status tests, including the Mini-Mental State Examination. The interobserver reliability of the CAM was high (kappa = 0.81 – 1.0). CONCLUSIONS: The CAM is sensitive, specific, reliable, and easy to use for identification of delirium.
2. Sands, M., B. Dantoc, et al. (2010). “Single Question in Delirium (SQiD): testing its efficacy against psychiatrist interview, the Confusion Assessment Method and the Memorial Delirium Assessment Scale.” Palliative Medicine 24(6): 561-565.
In this study we address the research question; How sensitive is a single question in delirium case finding? Of 33 ‘target’ admissions, consent was obtained from 21 patients. The single question: ‘Do you think [name of patient] has been more confused lately?’ was put to friend or family. Results of the Single Question in Delirium (SQiD) were compared to psychiatrist interview (ΨI) which was the reference standard. The Confusion Assessment Method (CAM) and two other tools were also applied. Compared with ΨI, the SQiD achieved a sensitivity and specificity of 80% (95% CI 28.3—99.49%) and 71% (41.90—91.61%) respectively. The CAM demonstrated a negative predictive value (NPV) of 80% (51.91—95.67%) and the SQiD showed a NPV of 91% (58.72—99.77%). Kappa correlation of SQiD with the ΨI was 0.431 (p = 0.023). The CAM had a kappa value of 0.37 (p = 0.050). A further important finding in our study was that the CAM had only 40% sensitivity in the hands of minimally trained clinical users. Conclusion: The SQiD demonstrates potential as a simple clinical tool worthy or further investigation.