Rosalind Lees

Test accuracy of cognitive screening tests for diagnosis of dementia and multidomain cognitive impairment in stroke.

Background and Purpose— Guidelines recommend screening stroke-survivors for cognitive impairments. We sought to collate published data on test accuracy of cognitive screening tools. Methods— Index test was any direct, cognitive screening assessment compared against reference standard diagnosis of (undifferentiated) multidomain cognitive impairment/dementia. We used a sensitive search statement to search multiple, cross-disciplinary databases from inception to January 2014. Titles, abstracts, and articles were screened by independent researchers. We described risk of bias using Quality Assessment of Diagnostic Accuracy Studies tool and reporting quality using Standards for Reporting of Diagnostic Accuracy guidance. Where data allowed, we pooled test accuracy using bivariate methods. Results— From 19 182 titles, we reviewed 241 articles, 35 suitable for inclusion. There was substantial heterogeneity: 25 differing screening tests; differing stroke settings (acute stroke, n=11 articles), and reference standards used (neuropsychological battery, n=21 articles). One article was graded low risk of bias; common issues were case–control methodology (n=7 articles) and missing data (n=22). We pooled data for 4 tests at various screen positive thresholds: Addenbrooke’s Cognitive Examination-Revised (<88/100): sensitivity 0.96, specificity 0.70 (2 studies); Mini Mental State Examination (<27/30): sensitivity 0.71, specificity 0.85 (12 studies); Montreal Cognitive Assessment (<26/30): sensitivity 0.95, specificity 0.45 (4 studies); MoCA (<22/30): sensitivity 0.84, specificity 0.78 (6 studies); Rotterdam-CAMCOG (<33/49): sensitivity 0.57, specificity 0.92 (2 studies). Conclusions— Commonly used cognitive screening tools have similar accuracy for detection of dementia/multidomain impairment with no clearly superior test and no evidence that screening tools with longer administration times perform better. MoCA at usual threshold offers short assessment time with high sensitivity but at cost of specificity; adapted cutoffs have improved specificity without sacrificing sensitivity. Our results must be interpreted in the context of modest study numbers: heterogeneity and potential bias.

Cognitive and Mood Assessment in Stroke Research Focused Review of Contemporary Studies

Background and Purpose— International guidelines recommend cognitive and mood assessments for stroke survivors; these assessments also have use in clinical trials. However, there is no consensus on the optimal assessment tool(s). We aimed to describe use of cognitive and mood measures in contemporary published stroke trials. Methods— Two independent, blinded assessors reviewed high-impact journals representing: general medicine (n=4), gerontology/rehabilitation (n=3), neurology (n=4), psychiatry (n=4), psychology (n=4), and stroke (n=3) January 2000 to October 2011 inclusive. Journals were hand-searched for relevant, original research articles that described cognitive/mood assessments in human stroke survivors. Data were checked for relevance by an independent clinician and clinical psychologist. Results— Across 8826 stroke studies, 488 (6%) included a cognitive or mood measure. Of these 488 articles, total number with cognitive assessment was 408 (83%) and mood assessment tools 247 (51%). Total number of different assessments used was 367 (cognitive, 300; mood, 67). The most commonly used cognitive measure was Folsteins Mini-Mental State Examination (n=180 articles, 37% of all articles with cognitive/mood outcomes); the most commonly used mood assessment was the Hamilton Rating Scale of Depression(n=43 [9%]). Conclusions— Cognitive and mood assessments are infrequently used in stroke research. When used, there is substantial heterogeneity and certain prevalent assessment tools may not be suited to stroke cohorts. Research and guidance on the optimal cognitive/mood assessment strategies for clinical practice and trials is required.

Test Accuracy of Short Screening Tests for Diagnosis of Delirium or Cognitive Impairment in an Acute Stroke Unit Setting

Background and Purpose— Guidelines recommend cognitive screening in acute stroke. Various instruments are available, with no consensus on a preferred tool. We aimed to describe test accuracy of brief screening tools for diagnosis of cognitive impairment and delirium in acute stroke. Methods— We collected data on sequential stroke unit admission in a single center. Four assessors trained in cognitive testing independently performed screening and reference tests. Brief assessments comprised the following: 10- and 4-point Abbreviated Mental Test (AMT-10; AMT-4); 4-A Test (4AT); Clock Drawing Test (CDT); Cog-4; and Glasgow Coma Scale (GCS). We also recorded the multidisciplinary team’s informal review using single question (SQ). We compared against reference standards of Montreal Cognitive Assessment (MoCA) and Confusion Assessment Method for delirium using usual diagnostic cutpoints. For MoCA, we described effects of lowering the diagnostic threshold to MoCA <24 and MoCA <20. We described sensitivity, specificity, and positive and negative predictive values. Results— Over a 10-week period, 111 subjects had cognitive assessment data. Subjects were 50% male (n=55), and median age was 74 years (interquartile range, 64–85). AMT-4, AMT-10, and SQ all had excellent (1.00) specificity for detection of cognitive impairment, although sensitivity was poor (all <0.60). The 4AT had greatest sensitivity for detecting delirium (1.00 [confidence interval [CI], 0.74–1.00]) and reasonable specificity (0.82 [CI, 0.72–0.89]). Properties of 4AT for detection of cognitive impairment, at the traditional MoCA threshold, were also good (sensitivity, 0.86; specificity, 0.78). Using diagnostic thresholds of MoCA ⩽26, <24, and <20 gave proportions with cognitive impairments of 86%, 61%, and 49%, respectively, with resulting changes in screening test properties. At lower MoCA thresholds, CDT had favorable sensitivity and specificity (MoCA <20: sensitivity, 0.93, specificity, 0.66; MoCA <24: sensitivity, 0.85, specificity, 0.77). Conclusions— Many brief screening assessments are specific but not sensitive for detection of cognitive impairment in acute stroke. Our primary analysis suggests that 4AT is a reasonable choice for delirium and cognitive screening in this setting. However, these data are based on standard MoCA diagnostic threshold and may not be suited for an acute stroke population.

Cognitive assessment in stroke: feasibility and test properties using differing approaches to scoring of incomplete items

Cognitive screening is recommended in stroke, but test completion may be complicated by stroke related impairments. We described feasibility of completion of three commonly used cognitive screening tools and the effect on scoring properties when cognitive testing was entirely/partially incomplete.

Questionnaire assessment of usual practice in mood and cognitive assessment in Scottish stroke units

Abstract Purpose: National and International guidelines recommend cognition and mood assessment for all stroke survivors. However, there is no consensus on preferred screening tool or method of assessment. We aimed to describe clinical practice in cognitive and mood assessment across Scottish stroke services. Method: We used a questionnaire based survey. After local piloting, we distributed the questionnaire using mixed methodologies (online and paper) across all Stroke Managed Clinical Networks in Scotland. We also distributed the questionnaire to specialist societies representing stroke physicians, nurses and allied health professionals and through the UK Stroke Forum delegate pack. Results: We received 174 responses from nurses, physiotherapists, psychologists, occupational therapists and medical staff. Medical staff made up the largest group of respondents (61, 35%). Of the respondents 148 (85%) routinely assess cognition and 119 (72%) mood. A variety of tools were used (cognitive n = 45 tools; mood n = 17); Mini Mental State Examination (n = 103, 59% of respondents) and the Hospital Anxiety and Depression Scale (n = 76, 44%) were the most commonly employed tools. Conclusion: Response rate was modest but included all mainland Scottish regions with active stroke services. Although the majority of responders are assessing cognition and mood there is substantial heterogeneity in measures used and certain commonly used tools are not validated or appropriate for use in stroke. We suggest development of evidence based, standardised assessment protocols. Implications for Rehabilitation Screening stroke survivor’s for cognitive and mood issues is recommended but there is little guidance on the preferred assessment strategy Across Scottish stroke services there is a lack of consensus in assessment and management of cognition and mood post stroke Sixty-two different cognitive/mood assessment tools were found to be in use across the country Careful consideration must be given when inspecting assessment tools and use of caution when interpreting results

Cog-4 has limited diagnostic test accuracy and validity for cognitive assessment in stroke survivors

BACKGROUND Guidelines recommend cognitive screening for all stroke survivors but do not suggest a preferred tool. Certain elements (orientation, executive function, language, and inattention) of the impairment scale, National Institutes of Health Stroke Scale (NIHSS), have been suggested as a short cognitive screening test-Cog-4. We aimed to describe accuracy and validity of Cog-4 against a more detailed cognitive assessment (Montreal Cognitive Assessment [MoCA]). METHODS We assessed consecutive acute stroke unit admissions in 2 hospitals over 3 months. Four independent blinded assessors performed NIHSS and MoCA between days 1 and 4 poststroke. We described test properties of Cog-4 for MoCA-defined cognitive impairment using usual thresholds (Cog-4≥1 and MoCA<26 of 30) and described the correlations of individual Cog-4 components with broadly equivalent MoCA domains. RESULTS We assessed 173 participants; 166 had Cog-4 data and 148 MoCA. MoCA described 84% (n=124) of assessed participants as having cognitive impairment and the Cog-4, 37% (n=62). Cog-4 had a sensitivity of .36 (95% confidence interval [CI]: .28-.45) and a specificity of .96 (95% CI: .80-.99) (positive predictive value: .98, negative predictive value: .23) for MoCA-defined cognitive impairment. Individual Cog-4 items correlated with certain MoCA domains, but the strength of association was modest (r=-.44 orientation, -.37 language, -.19 for inattention, and no significant correlation for executive function, P=.72). CONCLUSIONS Our data suggest that many stroke survivors with MoCA-defined cognitive problems would not be detected by Cog-4. Subtest correlations suggest that Cog-4 may not be a valid measure of the cognitive domains that it purports to describe. Other brief cognitive screening tests may be better suited to acute stroke.

AD-8 for diagnosis of dementia across a variety of healthcare settings

This is a protocol for a Cochrane Review (Diagnostic test accuracy). The objectives are as follows: To determine the diagnostic accuracy of the informant-based questionnaire AD-8, in detection of all-cause (undifferentiated) dementia in adults. We will present data for each healthcare setting where AD-8 may be employed (community; primary care; secondary care). AD-8 for diagnosis of dementia across a variety of healthcare settings (Protocol) Copyright