The Clock Reading Test: validation of an instrument for the diagnosis of dementia and disorders of visuo-spatial cognition

• Published in: International psychogeriatrics Vol. 19; no. 2; pp. 307 - 321
• Main Authors: Schmidtke, Klaus, Olbrich, Susanne
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.04.2007; Elsevier Inc
• Subjects: Adult and adolescent clinical studies; Aged; Alzheimer's disease; Biological and medical sciences; Clock Drawing Test; Cognition & reasoning; Cognition Disorders - diagnosis; Cognition Disorders - epidemiology; Cognitive ability; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Dementia; Dementia - epidemiology; diagnosis; Female; Geriatrics; Humans; Male; Medical diagnosis; Medical sciences; Middle Aged; Neurology; Neuropsychological Tests; neuropsychology; Organic mental disorders. Neuropsychology; Perceptual Disorders - diagnosis; Perceptual Disorders - epidemiology; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Reproducibility of Results; Severity of Illness Index; Space Perception - physiology; Time Perception; Visual Perception - physiology; Clock Drawing Test; neuropsychology; dementia; diagnosis; Alzheimer's disease; Human; Nervous system diseases; Alzheimer disease; Spatial cognition; Neuropsychological test; Psychometrics; Space perception; Cerebral disorder; Senile dementia; Test validation; Reading; Language; Central nervous system disease; Degenerative disease; Diagnosis; Neuropsychologia; Elderly
• ISSN: 1041-6102; 1741-203X
• DOI: 10.1017/S104161020600456X

Background: The 12-item Clock Reading Test (CRT) allows a fine-graded assessment of clock-reading ability. It has a strong focus on visuo-spatial processing and requires no executive processing. This study evaluated the reliability, validity, sensitivity and specificity of the CRT for the diagnosis of dementia and visuo-spatial dysfunction. Methods: The CRT, the Clock Drawing Test (CDT) and other tests were applied to groups of 200 subjects with dementia, 105 subjects with mild cognitive impairment (MCI), 20 subjects with focal parietal lesions and 64 elderly control subjects. Results: The CRT was found to be reliable and sensitive for the detection of cognitive impairment in parietal lesions, Alzheimer-, mixed- and Lewy Body dementia. Normal subjects and patients with MCI, frontotemporal dementia or cerebral small vessel disease showed little or no impairment. Conclusion: CRT and CDT are clock-processing tests with different demand profiles. They can supplement each other in the neuropsychological diagnosis of dementia and visuo-spatial dysfunction.