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Background: The clock drawing test (CDT) and the Mini Mental State Examination (MMSE) are frequently used screening instruments for cognitive impairment, however, the precise contribution of the CDT to the MMSE is largely unknown. Methods: We studied patients with subjective cognitive impairment (SCI, n = 481), mild cognitive impairment (MCI, n = 628) and Alzheimer's disease (AD, n = 1099). Discrimination between patients was examined with multiple logistic regression, adjusted for age, sex, and education. Four groups were constructed based on a normal/abnormal MMSE (cut‐off <24/30) versus normal/abnormal CDT (cut‐off ≤2/3). Visually rated medial temporal lobe atrophy (MTA) on CT was used as parameter of neurodegeneration. Results: The CDT significantly contributed to the MMSE in discriminating SCI from both MCI and AD patients. Our four group analyses showed that of those patients with a normal MMSE and incorrectly classified as SCI, an abnormal CDT could significantly identify 10.0% as MCI and 13.2% as AD. Among those with an abnormal MMSE, the percentage AD patients shifted from 53.1% to 82.1% due to an abnormal CDT. Presence of an abnormal CDT was significantly related to MTA increase, regardless of the MMSE score. Conclusion: The CDT is an important additional screening tool to the MMSE. An abnormal CDT with a normal MMSE is an indicator for cognitive impairment. An abnormal CDT in combination with an abnormal MMSE can be considered as an indicator of disease progression. Key points: The clock drawing test (CDT) is widely used as a screening tool for cognitive impairment, often in combination with the Mini Mental State Examination (MMSE), however, very few studies focus on the specific contribution of the CDT when the MMSE is known.To our knowledge, our study is the first to examine the additional value of the CDT to the MMSE in a large elderly memory clinic population to differentiate patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) from those with subjective cognitive impairment (SCI). We focus on the clinical use of both tests using predefined cut‐off scores.When patients have an MMSE of 24 or higher, and are thus classified as having no cognitive impairment by the MMSE, the CDT can significantly identify close to 25% as having either MCI or AD. When the MMSE is below 24, the combination with an abnormal CDT yielded a percentage of 82% AD.When the MMSE is known, an abnormal CDT can give additional information on progression along the SCI‐MCI‐AD trajectory. We therefore recommend the CDT as a highly relevant, quick and easy to administrate screening tool. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to clarify the diagnostic performance and neural basis of the Clock Drawing Test (CDT) combining free‐ and pre‐drawn methods. Methods: This retrospective study included 165 participants (91 with Alzheimer disease [AD], 52 with amnestic mild cognitive impairment [aMCI], and 22 healthy controls [HC]), who were divided into four groups according to their free‐ and pre‐drawn CDT scores: group 1, could do both; group 2, impaired in both; group 3, impaired in pre‐drawn CDT; and group 4, impaired in free‐drawn CDT. The diagnostic performances of the free‐drawn, pre‐drawn, and combination methods were compared using receiver operating characteristics analysis; in voxel‐based morphometry analysis, the gray matter (GM) volume of groups 2–4 were compared with that of group 1. Results: The area under the curve of the combination method was greater than that of the free‐ or pre‐drawn method alone when comparing AD with HC or aMCI. Group 2 had a significantly smaller GM volume in the bilateral temporal lobes than group 1. Group 3 had a trend toward smaller GM volumes in the right temporal lobe when a liberal threshold was applied. Group 4 had significantly smaller GM volumes in the left temporal lobe than group 1. Conclusions: This study suggests that the combination method may be able to screen for a wider range of brain dysfunction. Combined use of free‐ and pre‐drawn CDT may be useful for screening for AD and its early detection and treatment. Key points: The diagnostic performance and neural basis of the combination of free‐ and pre‐drawn Clock Drawing Test (CDT) were investigated in the Alzheimer disease [AD] continuum.The combination method is more sensitive than each method alone as a screening test for AD.The combination can screen for a wider range of brain dysfunction than each method alone. [ABSTRACT FROM AUTHOR]

Objective: The clock drawing test (CDT) has become one of the most widely used cognitive screening instruments in clinical and research settings. Its effectiveness, acceptability, and quick and easy administration have made it a staple for cognitive screening in dementia and a wide range of brain disorders. Despite a spike in popularity since the 1990s, its origins are relatively unknown. The goal of this review is to chronicle its saga and chart its usage over time.Methods: PsycInfo, Medline, and PubMed literature searches were performed from earliest record to June 2016, in addition to manual cross-referencing of bibliographies, with a focus before 1990. Summary of relevant articles and books up until 1989 is included, as well as clinical applications and surveys that track CDT usage over time.Results: While MacDonald Critchley's well-known textbook from 1953, The Parietal Lobes, is often cited as the first mention of the CDT, its recorded use actually stretches back more than a century to 1915. A review of the literature shows that the CDT began as a test for aphasia-related disorders and constructional apraxia until its entry into contemporary cognitive screening in the 1980s when it primarily became a cognitive screen. Its usage took off in 1989 with over 2000 publications since.Conclusions: Despite a fairly obscure existence for decades, the CDT has emerged as an effective and ideal cognitive screening instrument for a wide range of conditions. Its use continues to increase, and it has been incorporated into several widely used cognitive screening batteries. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives: The clock drawing test (CDT) is a commonly used brief cognitive measure. We evaluated diagnostic accuracy of subjective ratings of CDT by physicians (with/without specialty in cognitive neurology) and neuropsychologists in discriminating amnestic mild cognitive impairment (aMCI), Alzheimer's dementia (AD) and cognitively healthy older adults. We further compared the diagnostic accuracy of subjective categorical ratings with complex scoring of CDT.Methods: Three cognitive neurologists, three neuropsychologists and six neurology residents without experience in cognitive neurology blinded to the diagnosis rated 187 CDTs (50 mild AD, 49 aMCI and 88 cognitively healthy older adults) using a "yes" (abnormal) versus "suspected" versus "no" (normal) classification. The rating suspected was combined with yes or no to obtain two sets of sensitivity estimates. We also used a 17-point CDT rating system.Results: When using the categorical rating, neuropsychologists had highest sensitivity (89%) in differentiating patients with mild AD (yes/suspected versus no), followed by neurologic residents (80%) and cognitive neurologists (79%). When differentiating patients with aMCI (yes/suspected versus no), the sensitivity was 84% for neuropsychologists, 64% for cognitive neurologists and 62% for residents. The sensitivity using the complex scoring system was 92% in patients with mild AD and 69% in patients with aMCI.Conclusions: A categorical rating of CDT shows high sensitivity for mild AD even in non-experienced raters. Neuropsychologists outperformed physicians in differentiating patients with aMCI from cognitively healthy older adults (specificity), which was counterbalanced by the lower specificity of their ratings. The diagnostic accuracy was not substantially improved by using complex scoring system. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study is to examine the association of the clock drawing test (CDT) with incident dementia, cardiovascular events and mortality in very elderly hypertensive patients. Method All participants were hypertensive and aged 80 years and over. The CDT was administered at baseline and annually thereafter. Data on incident cardiovascular, fatal events and dementia were collected over follow-up. Results There were 3845 participants recruited and followed up for a mean of 2.1 years. Of these, 2701 completed a CDT with 2259 available at baseline. Of this group, 6.6% had a cardiovascular event, 6.1% died, and 10% were diagnosed with dementia. There was no relationship between baseline CDT score and subsequent cardiovascular events or mortality. For incident dementia, the hazard ratio was 0.88 (95% confidence intervals 0.83-0.94) suggesting that better performance on the baseline CDT was associated with a lower risk of dementia. Conclusion These results provide tentative support for the CDT alongside other cognitive screening tools in a hypertensive elderly population. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: In this study, we evaluated the effect on cognitive function of memantine, behavioral and psychological symptoms of dementia, and the care burden, in patients with moderate-to-severe Alzheimer’s disease (AD). Furthermore, with near-infrared spectroscopy (NIRS), we examined the association between effect of memantine and brain blood flow. Methods: We evaluated the effect of memantine administration from baseline on Clinical Global Impression-Improvement scale, mini mental state examination (MMSE), Clock Drawing Test (CDT), Neuropsychiatric Inventory (NPI), Japanese version of the Zarit Burden Interview (J-ZBI) and NIRS in two groups, donepezil administration memantine combination group (combination group, n = 19) donepezil administration memantine non-administration group (control group, n = 18) were assessed at weeks 0, 4, 12, and 24. Results: Significant difference was found between the combination group and the control group in the score variation of Clinical Global Impression-Improvement scale, MMSE, CDT, NPI, and J-ZBI. In the NIRS measurements, trend oxyhemoglobin reduced suppression was observed in some channels centered on the superior frontal gyrus. A significant correlation was observed in the scores of MMSE, CDT, NPI, and J-ZBI. In addition, a significant positive correlation was also observed between the number of words in NIRS and scores of MMSE and CDT. Conclusions: In this study, by administering memantine in AD patients that inhibit the reduction of cerebral blood flow in the prefrontal area and improve clinical symptoms overall cognitive function, behavioral and psychological symptoms of dementia, thereby reducing the care burden of caregivers was suggested. [ABSTRACT FROM AUTHOR]

Objective Earlier studies have demonstrated that a disintegrin and metallopeptidase 10 (ADAM10) levels are reduced in Alzheimer's disease (AD) patients compared with healthy subjects. The objective of this study was to evaluate whether platelet ADAM10 levels correlates with the clock drawing test (CDT) scores, which is a simple and a reliable measure of visuospatial ability and executive function in AD patients. Methods Thirty elderly patients with probable AD and 25 healthy patients forming the control group, matched by age, gender, and educational level, were evaluated. Platelet proteins were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis, and ADAM10 was identified by western blotting. The Spearman's correlation coefficient between ADAM10 and CDT was obtained for each group. The areas under the curves were used to compare the receiver operating characteristic curves. Results The CDT scores and platelet ADAM10 expression were significantly different between patients with AD and controls and also along the disease's progression. In AD patients, there was a positive correlation between ADAM10 expression and CDT scores. Among non-AD subjects, no correlation was found. The combination of ADAM10 and CDT was significantly better to confirm the AD diagnosis than the AUCs of ADAM10 and CDT separately. Conclusions The association of blood-based biomarkers, such as ADAM10, and cognitive tests may be helpful for a more reliable AD diagnosis. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective The clock drawing test (CDT) is a widely used cognitive screening tool that has been well accepted among clinicians and patients for its ease of use and short administration time. Although there is ample interest in the CDT as a screening instrument, there remains a range of CDT administration and scoring systems with no consensus on which system produces the most valid results while remaining user friendly. The aims of this review are to synthesize the available evidence on CDT scoring systems' effectiveness and to recommend which system is best suited for use at the clinical frontlines. Design A Pubmed literature search was carried out from 2000 to 2013 including manual cross-referencing of bibliographies in order to capture studies published after Shulman's comprehensive review published in 2000. A brief summary of all original scoring systems is included, as well as a review of relevant comparative studies. Results The consensus from multiple comparison studies suggests that increasing the complexity of CDT scoring systems does little to enhance the test's ability to identify significant cognitive impairment. Moreover, increased complexity in scoring adds to the administration time, thereby reducing the test's utility in clinical settings. Conclusions In comparing scoring systems, no system emerged as consistently superior in terms of predictive validity. The authors conclude that when scoring the CDT as a screening instrument in a primary/general medicine/community setting, simpler is better, and perhaps qualitative assessment of 'normal' versus 'abnormal' may be sufficient for screening purposes and the establishment of a baseline for follow-up. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: Earlier studies have demonstrated that a disintegrin and metallopeptidase 10 (ADAM10) levels are reduced in Alzheimer’s disease (AD) patients compared with healthy subjects. The objective of this study was to evaluate whether platelet ADAM10 levels correlates with the clock drawing test (CDT) scores, which is a simple and a reliable measure of visuospatial ability and executive function in AD patients. Methods: Thirty elderly patients with probable AD and 25 healthy patients forming the control group, matched by age, gender, and educational level, were evaluated. Platelet proteins were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis, and ADAM10 was identified by western blotting. The Spearman’s correlation coefficient between ADAM10 and CDT was obtained for each group. The areas under the curves were used to compare the receiver operating characteristic curves. Results: The CDT scores and platelet ADAM10 expression were significantly different between patients with AD and controls and also along the disease’s progression. In AD patients, there was a positive correlation between ADAM10 expression and CDT scores. Among non-AD subjects, no correlation was found. The combination of ADAM10 and CDT was significantly better to confirm the AD diagnosis than the AUCs of ADAM10 and CDT separately. Conclusions: The association of blood-based biomarkers, such as ADAM10, and cognitive tests may be helpful for a more reliable AD diagnosis. [ABSTRACT FROM AUTHOR]

Background The CAMCOG is a brief neuropsychological battery designed to assess global cognitive function and ascertain the impairments that are required for the diagnosis of dementia. To date, the cut-off scores for mild cognitive impairment (MCI) have not been determined. Given the need for an earlier diagnosis of mild dementia, new cut-off values are also necessary, taking into account cultural and educational effects. Methods One hundred and fifty-seven older adults (mean age: 69.6 ± 7.4 years) with 8 or more years of formal education (mean years of schooling 14.2 ± 3.8) attending a memory clinic at the Institute of Psychiatry University of Sao Paulo were included. Subjects were divided into three groups according to their cognitive status, established through clinical and neuropsychological assessment: normal controls, n = 62; MCI, n = 65; and mild or moderate dementia, n = 30. ROC curve analyses were performed for dementia vs controls, MCI vs controls and MCI vs dementia. Results The cut-off values were: 92/93 for dementia vs controls (AUC = 0.99: sensitivity: 100%, specificity: 95%); 95/96 for MCI vs controls (AUC = 0.83, sensitivity: 64%, specificity: 88%), and 85/86 for MCI vs dementia (AUC = 0.91, sensitivity: 81%, specificity: 88%). The total CAMCOG score was more accurate than its subtests Mini-mental State Examination, Verbal Fluency Test and Clock Drawing Test when used separately. Conclusions The CAMCOG discriminated controls and MCI from demented patients, but was less accurate to discriminate MCI from controls. The best cut-off value to differentiate controls and demented was higher than suggested in the original publication, probably because only cases of mild to moderate dementia were included. This is important given the need for a diagnostic at earlier stages of Alzheimer's disease. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective To determine the validity of the Clock Drawing Test (CDT) and the Mini-Mental State Examination (MMSE) respectively or in combination for differentiating Vascular Cognitive Impairment No Dementia (V-CIND) from normal subjects. Methods Eighty V-CIND patients and 80 healthy control subjects were blindly evaluated with MMSE, CDT, and additional neuropsychological tests. CDT was scored according to the Rouleau method and AD Cooperative Study method. Sensitivities and specificities of the two CDT measures and MMSE for identifying V-CIND patients were determined. The Areas Under the Receiver Operating Characteristic Curve (AUCs) were compared, and the sensitivity of the combination of CDT with MMSE calculated. Results V-CIND group performed worse than controls on both MMSE (p < 0.0001) and the two CDTs (p < 0.0001). In differentiating V-CIND patients from normal subjects, the two CDT measures provided sensitivities of 68.7% and 65.0%, and specificities of 78.7% and 86.2% respectively at optimal cutoff scores, which did no better than MMSE (sensitivity 80%, specificity 70%) (comparison of the AUCs, p = 0.992 and 0.428). The sensitivity of MMSE was marginally higher than that of CDT scored with AD Cooperative Study method (p = 0.053). By combining the two CDT measures with MMSE, the sensitivity was improved to 93.7% and 92.5% respectively. Conclusions Compared with MMSE, CDT is of only similar or even weaker ability for identifying V-CIND. MMSE at a cutoff of 28 may be of some value in detecting V-CIND patients. CDT and MMSE in combination provide a valid instrument for V-CIND screening. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ObjectivesIn order to evaluate the suitability of the clock drawing test (CDT) for the detection of questionable dementia (QD), we assessed the inter–rater reliabilities and intercorrelations of four common scoring methods of the CDT in a sample of non-demented subjects and determined the concurrent validity. MethodsThe study sample consisted of 253 discharged general hospital patients, aged between 65 and 85 years. Subjects were screened for cognitive impairment during their hospital stay. Four to six weeks after discharge each non-demented patient was visited at home and interviewed by a trained psychologist. The interview procedure included a cognitive test battery incorporating the CDT, the Mini-Mental State Examination (MMSE), the Syndrome Short Test (SKT), and a verbal fluency test (VF). The criteria of the Clinical Dementia Rating (CDR) were used to differentiate between cognitively normal subjects and those with QD. Clock drawings were scored independently and blindly by two raters according to four different methods. The agreement between raters was assessed, as well as the agreement between the different scoring methods. The association of gender, education, age, test performance and CDR-rating with CDT scores was examined. Accuracy of the CDT for the detection of QD was calculated. ResultsInter–rater reliabilities were high for all four scoring methods. However, substantial differences among the scoring methods were observed, the proportion of abnormal test results varying between 9% and 50%. The CDT correlated significantly with MMSE, SKT and VF, but correlation coefficients were low (r = 0.13 to r = 0.32). Furthermore, CDT scores were influenced by age, gender, and education. Sensitivity of the CDT for QD was 66%, specificity was 65%; the negative predictive value was 73%, the positive predictive value 58%. ConclusionIn a sample of non-demented elderly, the reliability of the CDT was sufficiently high, but the different scoring methods were not equivalent. When established cut-off scores were used, the proportion of abnormal CDTs were significantly different. Concurrent validity with other common cognitive tests was unsatisfactory. The CDT lacks sufficient sensitivity and specificity for the identification of QD and should not be used alone to screen for possible prodromal stages of dementing illnesses. The association of age, gender and level of education with CDT scores should be taken into account by clinicians using the CDT. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ObjectiveTo evaluate five different scoring methods of the Clock Drawing Test (CDT) and to examine whether a combination of Mini Mental State Examination (MMSE) or Short Performance Test (Syndrom Kurz Test, SKT), respectively, with CDT can be used for cognitive screening. MethodsRetrospective blinded analysis of clock drawing performance using five scoring methods (Shulman et al . (1986), Sunderland et al . (1989), Wolf-Klein et al . (1989), Watson et al . (1997), Manos (1997)). A Memory Clinic at an academic psychiatric hospital (University of Frankfurt am Main, Germany). 123 consecutive patients (79 dementia patients, 44 controls). Inter-rater reliability and correlation of five different scoring methods of the CDT with established psychometric tests. Sensitivity and specificity of all five CDT's using the original and modified cut-off scores. Sensitivity, specificity and positive and negative predictive value of a combination of the CDT with MMSE and SKT, respectively. ResultsAll scoring methods of the CDT showed a highly significant interrater reliability (0.82 to 0.94). Correlation with the MMSE and the SKT was also significant (p < 0.01) for all five CDTs. Highest sensitivity was achieved by the Shulman scoring method (81% sensitivity, specificity 79%). Sensitivity of all scoring methods could be improved up to 89% by modifying the originally proposed cut-off scores at the cost of lower specificity. By combining the CDT with the MMSE or the SKT, respectively, the sensitivity of each of the tests could be improved to 92% (SKT and Shulman scale). In patients with mild dementia (GDS 3), a combination of the Shulman Scale with the SKT (92%) and the MMSE (75%) achieved the highest sensitivity. ConclusionsThe CDT in combination with the MMSE or SKT is an easily administered, non threatening and highly sensitive screening test for dementia in the setting of a memory clinic. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Clock Drawing Test (CDT) is a recognized and accepted instrument for the early diagnosis of dementia in the elderly. In a prospective study we evaluated the association between the results of this test and a broad range of clinical, functional and sociodemographic variables. The study was conducted on elderly patients hospitalized for rehabilitation following stroke or hip fracture (HF) in the geriatric ward of a university hospital in southern Israel. The administration of the CDT and its scoring system were adapted from Sunderland et al . and Wolfe-Klein et al . The study was conducted on all 425 elderly patients who were hospitalized during the study period and who were capable of completing the test. Stepwise multiple regression was used to evaluate the association between the results of the CDT and the other variables. The mean CDT score (±SD) for the entire study population was 7.8±2.5 and 145 patients (34%) had scores of 6 or below. Of the 41 variables that were tested, significant associations with the CDT were found for the following four variables only: the Folstein minimental test (β=0.447, p <0.0001), the cognition value from the admission FIM (β=0.252, p <0.0001), years of education (β=0.183, p =0.0001), and the patient's age (β=-0.075, p =0.037). The total variance of the CDT explained by these four variables (Adjusted R [sup 2] ) was 0.554. We conclude that in the study population there was a significant proportion of patients with low CDT scores. This score, in this population, is influenced in particular by two other measures of cognitive function and by the formal level of education, together with a weaker effect of age. Copyright © 1999 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

No abstract is available for this article. [ABSTRACT FROM AUTHOR]