Addenbrooke’s Cognitive Examination III: Psychometric Characteristics and Relations to Functional Ability in Dementia

Objectives: The Addenbrooke’s Cognitive Examination (ACE) is a common cognitive screening test for dementia. Here, we examined the relationship between the most recent version (ACE-III) and its predecessor (ACE-R), determined ACE- III cutoff scores for the detection of dementia, and explored its relationship with functional ability. Methods: Study 1 included 199 dementia patients and 52 healthy controls who completed the ACE-III and ACE-R. ACE-III total and domain scores were regressed on their corresponding ACE-R values to obtain conversion formulae. Study 2 included 331 mixed dementia patients and 87 controls to establish the optimal ACE-III cutoff scores for the detection of dementia using receiver operator curve analysis. Study 3 included 194 dementia patients and their carers to investigate the relationship between ACE-III total score and functional ability. Results: Study 1: ACE-III and ACE-R scores differed by ≤1 point overall, the magnitude varying according to dementia type. Study 2: a new lower bound cutoff ACE-III score of 84/100 to detect dementia was identified (compared with 82 for the ACE-R). The upper bound cutoff score of 88/100 was retained. Study 3: ACE-III scores were significantly related to functional ability on the Clinical Dementia Rating Scale across all dementia syndromes, except for semantic dementia. Conclusions: This study represents one of the largest and most clini- cally diverse investigations of the ACE-III. Our results demonstrate that the ACE-III is an acceptable alternative to the ACE-R. In addition, ACE-III performance has broader clinical implications in that it relates to carer reports of functional impairment in most common dementias. (JINS, 2018, 24, 854–863

Adaption and Validation of the Addenbrooke’s Cognitive Examination (ACE-III) as a Cognitive Screening Tool for Dementia for Older Adults with Comorbid Hearing Impairment

Background: An association between dementia and age-related hearing loss has been consistently established, however current screening measures of cognitive performance may be affected by hearing loss. This potentially influences the accuracy of cognitive estimates. Aims: 1. To develop an adapted version of the Addenbrooke’s Cognitive Examination (ACE-III) for older adults with hearing loss, the HI-ACE-III. 2. To test the ability of the HI-ACE-III to distinguish individuals with a diagnosis of dementia from those without and establish an optimum cut-off. 3. To test HI-ACE-III subscales for convergent and divergent validity against standardised cognitive measures of relevant domains. Method: Adaption, carried out in consultation with experts and potential users, involved converting verbal instructions to visually presented instructions. Two groups of participants with hearing impairment over the age of 65 were recruited, the first were determined to be cognitively intact (HI group; n = 30), the second had an established dementia diagnosis (D-HI group; n = 16). The HI-ACE-III was administered along with additional visually presented cognitive tests; the Rey-Osterrieth Complex Figure (ROFC), Spatial Span (SS) and Graded Naming Test (GNT). Results: The ROC analysis revealed an Area Under the Curve (AUC) value of .960 for the HI-ACE-III, with an optimum cut-off point of <87, achieving 93.8% sensitivity and 93.3% specificity and likelihood ratio of dementia of 14.06:1. Concurrent validity was demonstrated through correlations between HI-ACE-III domain scores and relevant standardised neuropsychological measures. Internal consistency of the HI-ACE-III was verified with Cronbach’s alpha (α = .925). Conclusions: The HI-ACE-III showed good reliability, validity and diagnostic utility for dementia screening in older adults in a hearing impairment context. The adapted HI-ACE-III may offer an accurate and reliable indication of cognitive performance, supporting timely diagnosis of dementia and contributing to future research

An investigation into the reliability of the Addenbrooke’s Cognitive Examination-III (ACE-III) and clinical research portfolio

Background: Dementia is a leading cause of disability amongst older adults in the developed world. In recent years, an increasing emphasis has been placed on the early detection and diagnosis of dementia, and timely access to post-diagnostic support. Cognitive screening tests are essential tools in facilitating the process of early detection and dementia diagnosis and are currently widely used in clinical practice. The Addenbrooke’s Cognitive Examination-III (ACE-III) is one such tool. Despite it being recommended in several evidence-based guidelines and being widely used in the NHS, the rater reliability of the ACE-III has never been formally evaluated. Aims: To investigate rater accuracy in scoring the ACE-III both in terms of its total and sub-category scores across different raters and by the same raters at two different time points. A secondary exploratory analysis examines whether scoring accuracy is affected by participants’ experience of using the ACE-III and/or whether they have had formal training on how to administer and score the ACE-III. Methods: A filmed vignette of the ACE-III being administered to an older adult actor (mock patient) was used to assess scoring accuracy across different raters. The vignette has pre-determined ‘true’ scores. Participants were asked to view the filmed vignette whilst simultaneously completing an ACE-III scoring sheet. Following a two-month period, participants were invited back to view and score the same vignette again to assess intra-rater reliability. Participants were NHS staff working in Older People’s Community Mental Health Teams who routinely administer and score the ACE-III as part of their clinical practice. Results and Conclusions: The inter- and intra-rater scoring accuracy of the ACE-III is generally good, with error mainly accounted for by the domains which require more subjective judgements, namely, the visuospatial and language tests. Health professionals should therefore take these findings into account when scoring the ACE-III, and utilise the ACE-III administration and scoring guide to help improve accuracy. If all health professionals score the ACE-III in a consistent manner, the accurate and early identification and management of those individuals with a dementia will be improved

Sensitivity of the Mini-Mental State Examination, Montreal Cognitive Assessment and the Addenbrooke’s Cognitive Examination III to everyday activity impairments in dementia: An exploratory study

Objective: The Mini-Mental State Examination (MMSE) is one of the most frequently used cognitive measures for dementia severity, and linked to deficits in everyday functioning. Recently, the Montreal Cognitive Assessment (MoCA) and the Addenbrooke's Cognitive Examination III (ACE-III) increasingly substitute for the MMSE. However, there are no specific cut offs in the ACE-III for mild dementia. The objectives of this exploratory study were to assess the sensitivity of each scale to everyday functioning and to examine the cut offs between mild and moderate dementia on the ACE-III. Methods: People with mild dementia completed the MMSE, MoCA and ACE-III, whilst informal carers completed the Revised Interview for Deteriorations in Daily Living Activities for Dementia to rate their relative’s initiative and performance of instrumental activities of daily living, and the Katz activities of daily living scale. Data were analysed using correlation analysis, raw score comparisons, Cohen’s kappa and Receiver Operating Characteristics analysis. Results: Thirty-three dyads completed the measures. The ACE-III was the most sensitive tool for everyday functioning performance, whilst its language sub-scale was specifically related to initiation of activities. The most suitable cut off on the ACE-III between mild and moderate dementia was 61. Conclusions: Findings suggest ACE-III more efficiently identifies everyday functional impairments. Further research is required to confirm these exploratory analyses of the cut off between mild and moderate dementia on the ACE-III. Both functional impairment and stage of dementia are needed in the diagnostic process and in the clinical assessment of people with dementia

Dementia Screening Accuracy is Robust to Premorbid IQ Variation: Evidence from the Addenbrooke's Cognitive Examination-III and the Test of Premorbid Function

BACKGROUND: Scores on cognitive screening tools for dementia are associated with premorbid IQ. It has been suggested that screening scores should be adjusted accordingly. However, no study has examined whether premorbid IQ variation affects screening accuracy. OBJECTIVE: To investigate whether the screening accuracy of a widely used cognitive screening tool for dementia, the Addenbrooke's cognitive examination-III (ACE-III), is improved by adjusting for premorbid IQ. METHODS: 171 UK based adults (96 memory service attendees diagnosed with dementia and 75 healthy volunteers over the age of 65 without subjective memory impairments) completed the ACE-III and the Test of Premorbid Function (TOPF). The difference in screening performance between the ACE-III alone and the ACE-III adjusted for TOPF was assessed against a reference standard; the presence or absence of a diagnosis of dementia (Alzheimer's disease, vascular dementia, or others). RESULTS: Logistic regression and receiver operating curve analyses indicated that the ACE-III has excellent screening accuracy (93% sensitivity, 94% specificity) in distinguishing those with and without a dementia diagnosis. Although ACE-III scores were associated with TOPF scores, TOPF scores may be affected by having dementia and screening accuracy was not improved by accounting for premorbid IQ, age, or years of education. CONCLUSION: ACE-III screening accuracy is high and screening performance is robust to variation in premorbid IQ, age, and years of education. Adjustment of ACE-III cut-offs for premorbid IQ is not recommended in clinical practice. The analytic strategy used here may be useful to assess the impact of premorbid IQ on other screening tools

The validation of brief cognitive assessment tools to evaluate suspected dementia in Chinese-speaking populations

Background Around 20% of individuals living with dementia are from Chinese-speaking populations. Brief cognitive assessments can assist in the diagnosis of dementia, but it is unclear which are best for Chinese-speaking populations. Additionally, there is a pressing need to validate brief cognitive assessments in Taiwan. Aims I aimed, firstly, to critically examine evidence about brief ( 75% for sensitivity and specificity and < 75% for heterogeneity. I validated the Taiwanese version of the Addenbrooke's Cognitive Examination, ACE-III (T-ACE-III) with 90 participants in a Taiwanese memory clinic. I culturally adapted a brief cognitive assessment battery and determined its acceptability in Taiwan. Results My meta-analysis results found that the ACE-III and ACE-R were the only tests that met quality criteria across clinical populations for dementia and MCI. My empirical study showed that the T-ACE-III detected dementia in a Taiwanese population with a specificity of 100.0%, a sensitivity of 89.5%, and a Youden Index of 0.895, using an optimal cut-off value of 73/74. Conclusions The ACE-III and ACE-R demonstrated satisfactory psychometric properties for suspected dementia and MCI in Chinese-speaking populations. The T-ACE-III is an effective tool to help diagnose dementia in a Taiwanese clinical population. Further Research Building on my thesis publication, further research could examine T-ACE-III in dementia subtypes

Adaption and Preliminary Validation of the Addenbrooke’s Cognitive Examination‐III as a Screening Test for Mild Cognitive Impairment and Dementia in Hearing‐Impaired Individuals

Background: A large proportion of older adults assessed for cognitive impairment likely have hearing loss, potentially affecting accuracy of cognitive performance estimations. This study aimed to develop a hearing‐impaired version of the Addenbrooke’s Cognitive Examination‐III (HI‐ACE‐III) and to assess whether the HI‐ACE‐III can accurately distinguish people with Mild Cognitive Impairment (MCI) and dementia from cognitively intact controls. / Methods: The HI‐ACE‐III was developed by converting verbal instructions into a visual, timed PowerPoint presentation. 74 participants over the age of 60 were classified into three groups: 29 had MCI, 15 had mild to moderate dementia and 30 cognitively intact controls. Receiver Operating Characteristic (ROC) curves were graphed to test screening accuracy. Concurrent validity was examined through correlations between HI‐ACE‐III domain scores and relevant, visually presented standardised neuropsychological measures. / Results: ROC analysis for dementia revealed an Area Under the Curve (AUC) of 0.99, achieving excellent sensitivity (100%) and good specificity (93.3%) at an optimum cut‐off of <87. The AUC for MCI was 0.86, achieving reasonable sensitivity (75.9%) and good specificity (86.7%) at an optimum cut‐off of <92. HI‐ACE‐III subtests shared anticipated and statistically significant correlations with established measures of cognitive functioning. Internal consistency of the HI‐ACE‐III was excellent as verified with Cronbach’s alpha (α = .904). / Conclusion: Preliminarily, the HI‐ACE‐III showed good reliability, validity and screening utility for MCI and dementia in older adults in a hearing‐impairment context. The adapted HI‐ACE‐III may offer accurate and reliable indication of cognitive performance, supporting timely diagnosis and research examining links between hearing loss and cognitive decline

Validation of the Taiwanese Version of ACE-III (T-ACE-III) to Detect Dementia in a Memory Clinic

OBJECTIVE: The Addenbrooke's Cognitive Examination III (ACE-III) is a 100-points cognitive test used in detecting dementia in many countries. There has been no validation study of the ACE-III in patients with suspected dementia in a Taiwanese population, where the language is traditional Chinese. We aimed to culturally adapt and validate the ACE-III as a cognitive assessment tool for differentiating between people with and without dementia presenting to healthcare professionals in Taiwan with possible dementia. METHODS: We culturally adapted the ACE-III for Taiwan (T-ACE-III) and tested it with consenting patients with suspected dementia in northern Taiwan who had been through the diagnostic process. We calculated receiver operating characteristic (ROC) curves to test the ability of the T-ACE-III to differentiate between dementia and non-dementia cases using clinician diagnosis as the gold standard. We generated the Youden Index to determine the best cut-off score. RESULTS: We recruited 90 Taiwanese individuals aged 49-93 years: 24 males and 33 females had dementia and 12 males and 21 females did not. The area under the ROC curve was 0.99 for distinguishing dementia from non-dementia. The T-ACE-III had a sensitivity of 100% and specificity of 78.8% when the cut-off score was 86/87. With a cut-off value of 73/74, the specificity was 100.0%, and sensitivity 89.5%. The highest Youden Index was 0.895, indicating the best overall cut-off point to be 73/74. CONCLUSIONS: The T-ACE-III is an acceptable cognitive test with excellent psychometric properties for discriminating dementia from non-dementia in Taiwanese populations in memory clinic settings

Improving the quality of cognitive screening assessments: ACEmobile, an iPad-based version of the Addenbrooke's Cognitive Examination-III.

INTRODUCTION: Ensuring reliable administration and reporting of cognitive screening tests are fundamental in establishing good clinical practice and research. This study captured the rate and type of errors in clinical practice, using the Addenbrooke's Cognitive Examination-III (ACE-III), and then the reduction in error rate using a computerized alternative, the ACEmobile app. METHODS: In study 1, we evaluated ACE-III assessments completed in National Health Service (NHS) clinics (n = 87) for administrator error. In study 2, ACEmobile and ACE-III were then evaluated for their ability to capture accurate measurement. RESULTS: In study 1, 78% of clinically administered ACE-IIIs were either scored incorrectly or had arithmetical errors. In study 2, error rates seen in the ACE-III were reduced by 85%-93% using ACEmobile. DISCUSSION: Error rates are ubiquitous in routine clinical use of cognitive screening tests and the ACE-III. ACEmobile provides a framework for supporting reduced administration, scoring, and arithmetical error during cognitive screening

Reliability of Addenbrooke's Cognitive Examination III in differentiating between dementia, mild cognitive impairment and older adults who have not reported cognitive problems.

Diagnosing dementia can be challenging for clinicians, given the array of factors that contribute to changes in cognitive function. The Addenbrooke’s Cognitive Examination III (ACE-III) is commonly used in dementia assessments, covering the domains of attention, memory, fluency, visuospatial and language. This study aims to (1) assess the reliability of ACE-III to differentiate between dementia, mild cognitive impairment (MCI) and controls and (2) establish whether the ACE-III is useful for diagnosing dementia subtypes. Client records from the Northern Health and Social Care Trust (NHSCT) Memory Service (n = 2,331, 2013–2019) were used in the analysis including people diagnosed with Alzheimer’s disease (n = 637), vascular dementia (n = 252), mixed dementia (n = 490), MCI (n = 920) and controls (n = 32). There were significant differences in total ACE-III and subdomain scores between people with dementia, MCI and controls (p  73%) and thus the differences are not clinically relevant. The results suggest that ACE-III is a useful tool for discriminating between dementia, MCI and controls, but it is not reliable for discriminating between dementia subtypes. Nonetheless, the ACE-III is still a reliable tool for clinicians that can assist in making a dementia diagnosis in combination with other factors at assessment