Clock drawing test in screening for Alzheimer's dementia and mild cognitive impairment in clinical practice

Abstract

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.

Clock Drawing Test: A Simple Scoring System for the Accurate Screening of Cognitive Impairment in Patients with Mild Cognitive Impairment and Dementia

“…Our results are comparable with the results from previous studies done in Australia [14], Brazil [15], Canada [16], China [17], Czech Republic [9], Denmark [8], Germany [18], Greece [19], Italy [20][21][22], Israel [23], Portugal [24], Slovakia [25] and the USA [26][27][28]. The most interesting comparison is with the Austrian [29], Italian [20][21][22] and Czech [9] studiespopulations with whom we share a similar cultural and historical background.…”

“…In the Austrian study, where a 10-point scoring system was used, it was possible to identify patients with dementia, but not whether they had non-AD or AD dementia [29]. Our results were, therefore, more comparable with the results from the Czech Republic [9] and Italy [20], where the CDT was recognized as an appropriate test for screening purposes (Table 3). In most of the previous studies, more elaborate scoring systems were used, which perhaps renders them less suitable for screening purposes.…”

“…The most interesting comparison is with the Austrian [29], Italian [20][21][22] and Czech [9] studiespopulations with whom we share a similar cultural and historical background. In the Austrian study, where a 10-point scoring system was used, it was possible to identify patients with dementia, but not whether they had non-AD or AD dementia [29].…”

“…More complex systems may also lead to greater interrater variability. Vyhnálek et al [9] demonstrated that sensitivity of the CDT can differ by up to 20% if evaluated by neurologists or neuropsychologist.…”

“…The third, and most important difference, pertains to scoring systems. Different authors suggest different scoring systems, which may vary from 1 to 17 points [6,8,9]. Although a higher number of points may provide more accurate results, this is not necessarily always the case [8].…”