Addenbrookes Cognitive Examination Revised (ACE-R)

The diagnostic accuracy of Addenbrooke’s Cognitive Examination (ACE) as a brief ‘bedside’ cognitive screening instrument has led to its widespread adoption. Nonetheless, certain weaknesses have been identified in the ACE, prompting the development of the Addenbrooke’s Cognitive Examination-Revised (ACE-R). The ACE-R has been reported to have excellent sensitivities and specificities (>0.8) for the diagnosis of dementia at cut-off scores of 88/100 and 82/100 in the setting of a university hospital clinic.

Addenbrooke’s Cognitive Examination – Revised (ACE-R)

Addenbrook’s Cognitive Examination Scoring Manual

  • Maximum score of 100 weighted as follows:
    –         Orientation 10
    –         Attention 8
    –         Memory 35
    –         Verbal fluency 14
    –         Language 28
    –         Visuospatial ability 5
  • Raw scores are used for all items except for verbal fluency where a scaled scoring system for the letter and category fluency is utilized. (1)
  • Cut off score 88 or 83 (88 has higher sensitivity though). (1)
  • Able to differentiate between Alzheimer’s Disease (AD) and Frontotemporal Dementia (FTD) using VLOM ratio – if >3.2 likely AD, if <2.2 likely FTD.  (1)

Clinical Advantages of the ACE-R

  • Incorporates the questions on the MMSE and expands on the domains of memory, language and visuospatial concepts and adds tests of verbal fluency. (1)
  • Unlike other assessments (eg. CAMDEX or DRS) does not require specialized equipment or trained assessors. (1)
  • 15-20 minutes to administer. (4)
  • Sensitive to the early stages of Alzheimer’s (amnestic syndromes) and isolated frontal or linguistic deficits found in early frontotemporal dementia ie. Able to differentiate between AD and FTD, and in early stages of the disorders. (1)
  • Able to distinguish between patients with progressive degenerative disorders and those with affective disorders (eg. Major Depression.) The affective groups showed very little impairment in the total ACE scores, only mild deficits in memory and verbal fluency. (4)
  • Can detect cognitive impairment in atypical parkinsonian syndromes (Progressive Supranuclear Palsy, Multiple System Atrophy, Corticobasal Degeneration), opposed to MMSE, which cannot. Is as sensitive as DRS for this population. (3)

Clinical Disadvantages of ACE-R

  • Paucity of tests of executive functions. (2)
  • Some questions are associated withUKand countries with similar government systems (eg. asks for name of prime minister, leader of opposition.) (2)

Psychometric Properties

  • High internal consistency  – all its component scores contribute to the measurement of cognitive functions and correlate well with the composite score, which in turn determines the presence or absence of dementia. (1)
  • Construct validity was best for memory and verbal fluency showing good concordance with standard neuropsychological tests. (1)
  • Good construct validity for the diagnosis of dementia and had a high sensitivity, even with a lower cut-off score of 83. (1)
  • Detected dementia in 79% of patients – a third more than the MMSE when a cut-off score of 83 was used. And sensitivity of 93% when the cut-off of 88 is used. (1)
  • Particularly sensitive in the detection of FTD – nearly doubled the detection rate when compared with the MMSE. (1)
  • Age, level of education or gender does not influence the predictive outcome, compared to the MMSE where both age and gender have influential power. (1)

REFERENCES
(1)   Mathuranath, P.S; Nestor P.J; Berrios, G.E; Rakowicz, W. & Hodges, J.R. (2000) A brief cognitive test battery to differentiate Alzheimer’s disease and frontotemporal dementia. Neurology Vol 55 Issue 11, 1613-1620.
(2)   Cummings, J. (2000) New tests for dementia. Neurology Vol 55 Issue 11, 1601-1602.
(3)   Bak, T.H.; Rogers, T.T.; Crawford, L.M.; Hearn, V.C.; Mathuranath, P.S. & Hodges, J.R. (2005) Cognitive beside assessment in atypical parkinsonian syndromes. Journal of Neurology, Neurosurgery and Psychiatry Vol 76, 420-422.
(4)   Dudas, R; Berrios, G. & Hodges, J. (2005) The Addenbrooke’s Cognitive Examination (ACE) in the differential diagnosis of early dementias versus affective disorder. American Journal of Psychiatry Vol 13 Issue 3, 218-226.

Brock

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4 thoughts on “Addenbrookes Cognitive Examination Revised (ACE-R)

      • Hi Brock,
        I am currently completing my level II fieldwork at an inpatient psychiatric hospital, and have been asked to update their OT Admissions Assessment. Currently, their assessment consists of interviewing the patient to gather an occupational profile and administering parts of the KELS (Identification of Hazards, Basic Money and Math Skills, Use of Medical and Community Resources, and Telephone Use). A combination lock task used to be a part of the assessment to determine fine motor, problem solving, and short term memory, but was removed from the assessment due to an incident deeming the combination lock unsafe. Feedback from OT staff at my current fieldwork site regarding updates for their assessment has mostly focused on the addition of a “short, multi-step cognitive task that could function as the combination lock task had in the past”. “Standardized”, if possible. I have asked some of my peers who have completed their mental health fieldwork in similar settings, and most have told me that they administer the ACLS and the ADM in addition to gathering an occupational profile for each patient. Any feedback, suggestions, or information regarding standardized assessments used in this setting during admissions would be greatly appreciated!

  1. Having recently had this test applied to me, although i am not sure which version, may i point out 1 small flaw to be avoided.
    Having been given the test sheets to hold and look at, when i came to the end of spot the letters 🙂 the name and address i had been asked to remember was printed immediately below. Being that sort of person i looked down after the last letter , saw the details and read them out to my tester, commenting wittily. When she then took the sheets back and asked me to repeat that name and address it was of course simpler.
    When printing the test out, worth using an extra sheet of paper and moving the final memory/recall questions over i think.
    Many other personal questions such as age my parents died, father’s occupation etc were interspersed with the test questions but i remain unsure why as the tester had no way of gauging the validity of my answers

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