Clock‐drawing and dementia in the community: A longitudinal study

Abstract

SUMMARYThe clock-drawing test was used in a longitudinal study of 183 dementing individuals and their caregivers. Clockdrawing performance was measured by a simple standardized score which correlated significantly with other measures of cognitive function. Clock performance showed high individual consistency of performance as well as a significant deterioration from the initial level of performance to that obtained at 1-year follow-up. Dementing individuals who had experienced a significantly greater decline in clock-drawing performance at 1 -year follow-up were more likely to have caregivers who had already decided to institutionalize them. This suggests that the caregiver's decision to institutionalize was based in part on the perception of a rapid decline in their dependant's cognitive function. Thus, rate of change in cognitive function may prove to be as important a variable as the level of deterioration. The clock-drawing test appears to be a useful adjunct in the assessment and monitoring of the progressive dementias in the community.KEY woms-Clock-drawing, dementia, community, longitudinal.The utility of the clock-drawing test in the assessment of dementia has been investigated in a number of recent studies (Shulman et al., 1986;Sunderland et al., 1989;Wolf-Klein et al., 1989;Dastoor et al., 1991;Huntzinger et al., 1992;Tuokko et al., 1992). Clock-drawing appears to subsume a diverse range of higher-level cognitive abilities including visuospatial organization, integrative functions and abstract thinking. Because of the wide range of intellectual functions tapped by the clock-drawing test it is particularly suited for the purpose of assessing global cognitive function and reflecting subtle changes in overall brain functioning. As the test is still in its early stages of development, a variety of scoring systems have been used. While there is still no system that is widely accepted, Dastoor (1992) recently confirmed the test's usefulness in differentiating Alzheimer's disease from normal ageing changes. They used a more detailed scoring system dividing performance into three categories including clockdrawing, setting and reading.Clock-drawing as a measure of cognitive function is appealing for a number of practical reasons. It is easy to administer and well tolerated by patients and does not appear to be noticeably influenced by language, cultural, ethnic or educational factors. Since it provides a graphic measure of cognitive function it is useful in chart review and clinical follow-up. For clinicians and epidemiologists alike, a short easily administered test that correlates well with other more detailed and timeconsuming cognitive screens is attractive (Huntz-

The Clock Drawing Test: performance among elderly with low educational level

“…A clock drawing task is part of this instrument and uses the following instruction: "Draw the face of a large clock, place all the numbers inside and place the pointers indicating 11:10 (eleven hours and ten minutes)". The clock drawing of each patient -copied and identified with its respective register number -was analyzed retrospectively by five researchers who had no access to the patient's file and were unaware of the cognitive condition of the subjects; each researcher applied one of the following four methods: Manos, 11 Shulman et al, 12 Wolf-Klein et al 13 and Sunderland et al 14 proposals. The fifth researcher applied the Manos method, 11 and thus this test was assessed by two researchers with the aim of evaluating its inter-rater reliability.…”

“…The researchers standardized these different methods by three procedures: 1) reading of the original texts with the description of the items and subsequent studies that used them; 2) intense discussion about the operational aspects to establish standardization in the instrument's application; 3) a pilot project with 35 clock drawings which confirmed that the standardization of these four methods among the members of the research team was excellent. The intraclass correlation coefficient (ICC) results were: 0.96 (95% CI 0.88-0.98); 0.95 (95% CI 0.90-0.98); 0.89 (95% CI 0.79-0.95); 0.97 (95% CI 0.95-0.99) for the Manos, 11 Shulman et al, 12 Wolf-Klein et al, 13 and Sunderland et al…”

“…The Clock Drawing Test (CDT) [10][11][12][13][14] satisfies most of these conditions, and is considered relatively resistant to educational and ethnic diversity, although the available data do not support this observation conclusively. 15,16 Many studies have shown that the CDT is useful as a screening test for cognitive impairment, especially in populations with higher educational levels (8 years or more).…”

“…The objectives of the present study were: 1) to compare the accuracy -sensitivity, specificity, and area under the curve -of four CDT scoring systems (Manos, 11 Shulman,12 Wolf-Klein, 13 Sunderland 14 ); 2) to determine the inter-rater reliability of one of these methods (Manos 11 ); and 3) to determine the influence of schooling on the CDT accuracy as a screening test for dementia in a population of older people treated in a primary care outpatient clinic, where low educational levels predominate.…”

The test of time: a history of clock drawing

“…Many of these scoring systems have also been tailored specifically to detect impairment related to specific disorders (Mendez et al, 1992;Rouleau et al, 1992). Some scoring systems follow a set of clear quantitative guidelines that outline certain components of the CDT that should be scored individually (i.e., number placement and number spacing) (Mendez et al, 1992), while some follow a more abstract qualitative guideline for scoring (i.e., minor visuospatial errors and severe level of disorganization) (Shulman et al, 1993). Despite the variability in scoring systems, it has been shown that simpler scoring systems are often better (Mainland and Shulman, 2013).…”