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Background: The Clock Drawing Test (CDT) is used to screen for Alzheimer's disease and other dementia disorders. Normative scores on the version from the Montreal Cognitive Assessment (MoCA) do not exist in the Nordic countries. Objective: To examine the normative scores of the CDT among adults aged 70 years and older. Methods: We included 4,023 cognitively healthy persons aged 70–97 years from a population survey in Norway. They were examined with the CDT, which has a total score between zero and three. A multiple multinominal regression model was applied with a CDT score as the dependent categorical variable and estimated the probabilities of scoring a particular score, stratified by age, sex, and education. These probabilities correspond to an expected proportion of the normative population scoring at, or below a given percentile. Results: None scored zero, 2.1% scored one, 14.9% scored two, and 83% scored three. Higher age, female sex and fewer years of schooling were associated with poorer performance. Scores of zero and one deviated from the normative score regardless of age, sex and education. A score of two was within the norm for a female older than 81 and a male older than 85. Conclusions: The majority (83%) of people 70 years and older had a score of three on the CDT. Lower age, male sex, and higher education were associated with a better performance. Scores of zero and one were below the normative score. Except for the very old, a score of two was also well below the normative score. [ABSTRACT FROM AUTHOR]

Neuropsychological assessment using the Boston Process Approach (BPA) suggests that an analysis of the strategy or the process by which tasks and neuropsychological tests are completed, and the errors made during test completion convey much information regarding underlying brain and cognition and are as important as overall summary scores. Research over the last several decades employing an analysis of process and errors has been able to dissociate between dementia patients diagnosed with Alzheimer's disease, vascular dementia associated with MRI-determined white matter alterations, and Parkinson's disease; and between mild cognitive impairment subtypes. Nonetheless, BPA methods can be labor intensive to deploy. However, the recent availability of digital platforms for neuropsychological test administration and scoring now enables reliable, rapid, and objective data collection. Further, digital technology can quantify highly nuanced data previously unobtainable to define neurocognitive constructs with high accuracy. In this paper, a brief review of the BPA is provided. Studies that demonstrate how digital technology translates BPA into specific neurocognitive constructs using the Clock Drawing Test, Backward Digit Span Test, and a Digital Pointing Span Test are described. Implications for using data driven artificial intelligence-supported analytic approaches enabling the creation of more sensitive and specific detection/diagnostic algorithms for putative neurodegenerative illness are also discussed. [ABSTRACT FROM AUTHOR]

Background: Relative to the abundance of publications on dementia and clock drawing, there is limited literature operationalizing 'normal' clock production.Objective: To operationalize subtle behavioral patterns seen in normal digital clock drawing to command and copy conditions.Methods: From two research cohorts of cognitively-well participants age 55 plus who completed digital clock drawing to command and copy conditions (n = 430), we examined variables operationalizing clock face construction, digit placement, clock hand construction, and a variety of time-based, latency measures. Data are stratified by age, education, handedness, and number anchoring.Results: Normative data are provided in supplementary tables. Typical errors reported in clock research with dementia were largely absent. Adults age 55 plus produce symmetric clock faces with one stroke, with minimal overshoot and digit misplacement, and hands with expected hour hand to minute hand ratio. Data suggest digitally acquired graphomotor and latency differences based on handedness, age, education, and anchoring.Conclusion: Data provide useful benchmarks from which to assess digital clock drawing performance in Alzheimer's disease and related dementias. [ABSTRACT FROM AUTHOR]

Background: The ongoing scientific debate regarding the association between physical function and cognitive impairment has focused mainly on global cognitive performance rather than specific cognitive functions tests and the importance of recognition of its associations and any factors that could play a role later in the prevention of such decline.Objective: This study examined the association between physical function, using handgrip strength (HGS) and Timed Up-and-Go test (TUGT), and executive function (EF), using Clock Drawing Test (CDT), among community-dwelling Egyptian elderly.Methods: A cross-sectional study was conducted in 5 social clubs in Cairo, Egypt and included a sample of 136 elderly males and females aged≥55 years old. All participants had their physical function assessed using TUGT, and measurement of HGS using a pneumatic hand-held dynamometer. Assessment of EF using CDT was also done.Results: Higher CDT scores were significantly associated with both better HGS, and lower TUGT (OR = 3.77, and 0.65 respectively). This persisted even after adjustment for age and gender (OR = 2.56, and 0.71 respectively) and after further adjustment for weight, systolic blood pressure, education, smoking, hyperlipidemia, hypothyroidism, and physical activity (O.R. = 4.79, and 0.76 respectively). Adjustment for both male and female genders showed an association between physical (HGS and TUGT) and EF was stronger among men.Conclusion: A strong association between CDT score and both of HGS and TUGT was found among the studied sample. Higher HGS and lower TUGT was significantly associated with better performance in the CDT. This association is stronger in males than in females for both HGS and TUGT. [ABSTRACT FROM AUTHOR]

Background: Differentiating mild cognitive impairment (MCI) from subjective cognitive decline (SCD) is important because of the higher progression rate to dementia for MCI and when considering future disease-modifying drugs that will have treatment indications at the MCI stage.Objective: We examined if the two most widely-used cognitive tests, the Mini-Mental State Examination (MMSE) and clock-drawing test (CDT), and a test of attention/executive function (AQT) accurately can differentiate MCI from SCD.Methods: We included 466 consecutively recruited non-demented patients with cognitive complaints from the BioFINDER study who had been referred to memory clinics, predominantly from primary care. They were classified as MCI (n = 258) or SCD (n = 208) after thorough neuropsychological assessments. The accuracy of MMSE, CDT, and AQT for identifying MCI was examined both in training and validation samples and in the whole population.Results: As a single test, MMSE had the highest accuracy (sensitivity 73%, specificity 60%). The best combination of two tests was MMSE < 27 points or AQT > 91 seconds (sensitivity 56%, specificity 78%), but in logistic regression models, their AUC (0.76) was not significantly better than MMSE alone (AUC 0.75). CDT and AQT performed significantly worse (AUC 0.71; p < 0.001-0.05); otherwise no differences were seen between any combination of two or three tests.Conclusion: Neither single nor combinations of tests could differentiate MCI from SCD with adequately high accuracy. There is a great need to further develop, validate, and implement accurate screening-tests for primary care to improve accurate identification of MCI among individuals that seek medical care due to cognitive symptoms. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease dementia (ADD) has become an important health problem in the world. Visuospatial deficits are considered to be an early symptom besides memory disorder.Objectives: The gesture imitation test was devised to detect ADD and amnestic mild cognitive impairment (aMCI).Methods: A total of 117 patients with ADD, 118 with aMCI, and 95 normal controls were included in this study. All participants were administered our gesture imitation test, the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), the Clock Drawing Test (CDT), and the Clinical Dementia Rating Scale (CDR).Results: Patients with ADD performed worse than normal controls on global scores and had a lower success rate on every item (p < 0.001). The area under the curve (AUC) for the global scores when comparing the ADD and control groups was 0.869 (p < 0.001). Item 4 was a better discriminator with a sensitivity of 84.62% and a specificity of 67.37%. The AUC for the global scores decreased to 0.621 when applied to the aMCI and control groups (p = 0.002). After controlling for age and education, the gesture imitation test scores were positively correlated with the MMSE (r = 0.637, p < 0.001), the MoCA (r = 0.572, p < 0.001), and the CDT (r = 0.514, p < 0.001) and were negatively correlated with the CDR scores (r = -0.558, p < 0.001).Conclusions: The gesture imitation test is an easy, rapid tool for detecting ADD, and is suitable for the patients suspected of mild ADD and aMCI in outpatient clinics. [ABSTRACT FROM AUTHOR]

Background: The Institute of Cognitive Neurology (INECO) Frontal Screening (IFS) is a brief neuropsychological tool recently devised for the evaluation of executive dysfunction in neurodegenerative conditions. Objective: In this study we present a cross-cultural validation of the IFS for the Portuguese population, provide normative values from a healthy sample, determine how age and education affect performance, and inspect its clinical utility in the context of Alzheimer's disease (AD). A comparison with the Frontal Assessment Battery (FAB) was undertaken, and correlations with other well-established executive functions measures were examined. Methods: The normative sample included 204 participants varying widely in age (20-85 years) and education (3-21 years). The clinical sample (n = 21) was compared with a sample of age- and education-matched controls (n = 21). Healthy participants completed the IFS and the Mini-Mental State Examination (MMSE). In addition to these, the patients (and matched controls) completed the FAB and a battery of other executive tests. Results: IFS scores were positively affected by education and MMSE, and negatively affected by age. Patients underperformed controls on the IFS, and correlations were found with the Clock Drawing Test, Stroop test, and the Zoo Map and Rule Shift Card tests of the Behavioral Assessment of the Dysexecutive Syndrome. A cut-off of 17 optimally differentiated patients from controls. While 88% of the IFS sub-tests discriminated patients from controls, only 67% of the FAB sub-tests did so. Conclusion: Age and education should be taken into account when interpreting performance on the IFS. The IFS is useful to detect executive dysfunction in AD, showing good discriminant and concurrent validities. [ABSTRACT FROM AUTHOR]

Background: The Clock Drawing Test (CDT) is a widely-used, rapid assessment tool for the screening of cognitive decline though its evaluation and interpretation are still not uniform. The aim of present study was to investigate the difference in sensitivity and specificity of two types of CDTs and to compare the clinical benefits of quantitative and semiquantitative scoring systems. Objective: To investigate the difference in sensitivity and specificity of two types of CDTs and to compare the clinical benefits of quantitative and semiquantitative scoring systems. Methods: Six hundred and ninety-two participants with or without dementia completed 10-item CDTs in nursing homes in two counties in southern Hungary. The dementia was not further subclassified. The results of the two tests, CDT1 (representing five minutes to a quarter to four) and CDT2 (representing ten past five), were evaluated quantitatively and semiquantitatively. Results: In the quantitative evaluation, the sensitivity and the specificity for the diagnosis of dementia at cut-off scores of 7 points were determined: 87.1% and 51.9%, respectively, for CDT1, and 81.7% and 57% for CDT2, respectively. The semiquantitative analysis revealed a sensitivity of 67.3% and a specificity of 65.3% for CDT1, and of 64.6% and 66.6% for CDT2, respectively. Conclusion: The results of CDT tests do not appear to depend on the positions of the clock hands and additionally suggest that the quantitative evaluation method is more sensitive than the semiquantitative method. [ABSTRACT FROM AUTHOR]

There is currently a need to develop tools to identify patients with mild AD and mild cognitive impairment (MCI). We determined the validity and reliability of a brief, easily administered cognitive screening battery consisting of fusion of two well-known brief tests (Mini-Mental Status Examination [MMSE] and Clock Drawing Test [CDT]) (Mini-clock) to differentiate between patients with mild AD, MCI, and healthy control subjects. 66 consecutive patients with mild AD, 21 with MCI, and 66 healthy controls seen in a memory clinic setting were compared. Receiver operating characteristic (ROC) curve analysis was used to calculate the cut-off value permitting discrimination between mild AD, MCI, and healthy control subjects. Interrater and test-retest reliability were also assessed. Mean cognitive scores for patients with AD, MCI, and control subjects on all two individual tests were significantly different (for each, p < 0.001). The mean area under the ROC curve for Mini-clock was higher than that obtained with MMSE or CDT in differentiating mild AD from controls (0.973 vs. 0.952 and 0.881, respectively) and MCI from controls (0.855 vs. 0.821 and 0.779, respectively). Test-retest reliability for the Mini-clock was 0.99, meanwhile interrater reliability was 0.87. The mean time to complete the test for all subjects was 8 min and 50 s. The Mini-clock is highly sensitive and specific in the detection of mild AD and reasonably accurate when attempting to separate MCI from health controls. It has a high interrater and test-retest reliability, can be quickly administered, and does not require major training. [ABSTRACT FROM AUTHOR]