The Standardization of the Clock Drawing Test (CDT) for People with Stroke Using Rasch Analysis

Limits on using the clock drawing test as a measure to evaluate patients with neurological disorders

BACKGROUND

The Clock Drawing Test (CDT) is used as a quick-to-conduct test for the diagnosis of dementia and a screening tool for cognitive impairments in neurological disorders. However, the association between the pattern of CDT impairments and the location of brain lesions has been controversial. We examined whether there is an association between the CDT scores and the location of brain lesions using the two available scoring systems.

METHOD

One hundred five patients with brain lesions identified by CT scanning were recruited for this study. The Montreal Cognitive Assessment (MoCA) battery including the CDT were administered to all partcipants. To score the CDT, we used a qualitative scoring system devised by Rouleau et al. (1992). For the quantitative scoring system, we adapted the algorithm method used by Mendes-Santos et al. (2015) based on an earlier study by Sunderland et al. (1989). For analyses, a machine learning algorithm was used.

RESULTS

Remarkably, 30% of the patients were not detected by the CDT. Quantitative and qualitative errors were categorized into different clusters. The classification algorithm did not differentiate the patients with traumatic brain injury 'TBI' from non-TBI, or the laterality of the lesion. In addition, the classification accuracy for identifying patients with specific lobe lesions was low, except for the parietal lobe with an accuracy of 63%.

CONCLUSION

The CDT is not an accurate tool for detecting focal brain lesions. While the CDT still is beneficial for use with patients suspected of having a neurodegenerative disorder, it should be cautiously used with patients with focal neurological disorders.

Clinical usefulness of the clock drawing test applying rasch analysis in predicting of cognitive impairment

[Purpose] This study examined the clinical usefulness of the clock drawing test applying Rasch analysis for predicting the level of cognitive impairment. [Subjects and Methods] A total of 187 stroke patients with cognitive impairment were enrolled in this study. The 187 patients were evaluated by the clock drawing test developed through Rasch analysis along with the mini-mental state examination of cognitive evaluation tool. An analysis of the variance was performed to examine the significance of the mini-mental state examination and the clock drawing test according to the general characteristics of the subjects. Receiver operating characteristic analysis was performed to determine the cutoff point for cognitive impairment and to calculate the sensitivity and specificity values. [Results] The results of comparison of the clock drawing test with the mini-mental state showed significant differences in according to gender, age, education, and affected side. A total CDT of 10.5, which was selected as the cutoff point to identify cognitive impairement, showed a sensitivity, specificity, Youden index, positive predictive, and negative predicive values of 86.4%, 91.5%, 0.8, 95%, and 88.2%. [Conclusion] The clock drawing test is believed to be useful in assessments and interventions based on its excellent ability to identify cognitive disorders.

Effects of spaced retrieval training with errorless learning in the rehabilitation of patients with dementia

[Purpose] Among the non-pharmacological interventions for dementia, spaced retrieval training (SRT) is a good method for rehabilitating cognition. The purpose of this study was to examine effects of SRT with errorless learning (EL) in the rehabilitation of patients with dementia. [Subjects and Methods] Twenty-nine participants with vascular dementia (VD) and Alzheimer’s disease (AD) participated in the present study. The Korean version of the Consortium to Establish a Registry for Alzheimer’s disease (CERAD-K) and Modified Barthel Index (MBI) were performed to assess the changes in the neuropsychological performance and the independent activities of daily living after SRT with EL. All tests were administered both before and after SRT with EL. Each SRT with EL intervention was performed for 30 minutes per day for 5 weeks. SPSS for Windows version 18.0 was used for statistical analysis. [Results] All items of the CERAD-K score of the VD group except for constructional praxis increased significantly after the SRT with EL intervention, but no significant differences from the AD group were found. The Korean version of the geriatric depression scale (GDS-K) of the VD group increased significantly after the SRT with EL intervention. The mean MBI scores of each group showed no significant difference after the intervention. [Conclusion] SRT with EL is an effective intervention for memory training of patients with dementia. Future research using sufficient sample sizes will be needed to obtain strong evidence for comparing not only the before and after intervention data but also between the groups.