The Clock Drawing Test (CDT) is a simple neuropsychological screening instrument that is well accepted by patients and has solid psychometric properties. Several different CDT scoring methods have been developed, but no consensus has been reached regarding which scoring method is the most accurate. This article reviews the literature on these scoring systems and the changes they have undergone over the years. Historically, different types of scoring systems emerged. Initially, the focus was on screening for dementia, and the methods were both quantitative and semi-quantitative. Later, the need for an early diagnosis called for a scoring system that can detect subtle errors, especially those related to executive function. Therefore, qualitative analyses began to be used for both differential and early diagnoses of dementia. A widely used qualitative method was proposed by Rouleau et al. (1992). Tracing the historical path of these scoring methods is important for developing additional scoring systems and furthering dementia prevention research.

The Clock Drawing Test (CDT) is an inexpensive, fast and easily administered measure of cognitive function, especially in the elderly. This instrument is a popular clinical tool widely used in screening for cognitive disorders and dementia. The CDT can be applied in different ways and scoring procedures also vary.ObjectiveThe aims of this study were to analyze the performance of elderly on the CDT and evaluate inter-rater reliability of the CDT scored by using a specific algorithm method adapted from Sunderland et al. (1989).MethodsWe analyzed the CDT of 100 cognitively normal elderly aged 60 years or older. The CDT ("free-drawn") and Mini-Mental State Examination (MMSE) were administered to all participants. Six independent examiners scored the CDT of 30 participants to evaluate inter-rater reliability.Results and ConclusionA score of 5 on the proposed algorithm ("Numbers in reverse order or concentrated"), equivalent to 5 points on the original Sunderland scale, was the most frequent (53.5%). The CDT specific algorithm method used had high inter-rater reliability (p<0.01), and mean score ranged from 5.06 to 5.96. The high frequency of an overall score of 5 points may suggest the need to create more nuanced evaluation criteria, which are sensitive to differences in levels of impairment in visuoconstructive and executive abilities during aging.

The Clock Drawing Test (CDT) is a frequently employed screening tool with different scoring systems. Quantitative and semi-quantitative scoring systems, such as Sunderland’s et al. (1989), do not discriminate different error patterns. Thus, the same score can represent a number of different neuropsychological profiles. Therefore, the use of a scoring method that emphasizes qualitative aspects to determine specific error patterns is fundamental.Objective:To use a qualitative scale to analyze error patterns in the CDTs of older adults who scored 5 in a previous study.Methods:49 CDTs with score of 5 were analyzed using the qualitative scale. Linear regression and hierarchical and non-hierarchical cluster analyses were performed.Results:The linear regression showed a significant association between the total score and all the error patterns of the qualitative scale. The hierarchical cluster yielded three groups. However, due to the heterogeneity observed among the groups, a non-hierarchical cluster analysis was performed to better understand the results. Three groups were determined with different neuropsychological profiles and patterns of errors.Conclusion:The qualitative scoring of the CDT is important when examining and analyzing specific neuropsychological domains in older adults, especially executive functions.