Clock Drawing Test-Modified and Integrated Approach (CDT-MIA): description and preliminary examination of its validity and reliability in dementia patients referred to a specialized psychogeriatric setting.

The authors developed a scoring system for clock drawing, based on modification and integration of 3 established scoring methods. The Clock Drawing Test-Modified and Integrated Approach (CDT-MIA) is a 4-step, 20-item instrument, with a maximum score of 33, which emphasizes differential scoring of contour, numbers, hands, and center. It was administered to 139 patients (93 with and 46 without dementia). Dementia patients revealed significantly more impairment on the CDT-MIA total score and hours and hands subscores. Correlations between CDT-MIA and 2 CDTs were high. With receiver operating characteristics (ROC) curves, the area constructed under CDT-MIA curve was large. The best trade-off between sensitivity and specificity for CDT-MIA was the cut-point 23 (91% and 80%, respectively). The internal consistency of CDT-MIA was high, and there was a high degree of interrater reliability. Thus, CDT-MIA was found to be a valid and reliable evaluation instrument for dementia patients in a specialized setting.

Can clock drawing test help to differentiate between dementia of the Alzheimer's type and vascular dementia? A preliminary study.

OBJECTIVES: the purpose of this preliminary study was to determine if clock drawing performance may help to differentiate between dementia of the Alzheimer's type (DAT) and vascular dementia (VD) patients. METHODS: eighty-eight community-dwelling outpatients were comprehensively evaluated and met DSM-IV criteria for DAT or VD. Cognitive evaluation included the Mini-Mental State Examination (MMSE) and the Cambridge Cognitive Examination (CAMCOG). CAMCOG derived clock drawings were blindly evaluated by the same investigator, according to Freedman's method for clock drawing, and a total score as well as subscores (contour, numbers, hands and center) were determined. RESULTS: There were no significant differences between DAT and VD patients in terms of demographic (age, gender, education) and cognitive (MMSE score, CAMCOG score) characteristics. On the average, the VD group showed slightly poorer performance on each of the clock drawing test (CDT) measures studied. With application of the Bonferroni correction, only Freedman's total score and hands subscore were statistically different between groups (p<0.003, p<0.004, respectively). Stepwise logistic regression analyses showed that the only significant variable was Freedman's total score (B=-0.273, p=0.005). Stepwise discriminant analysis identified Freedman's total score as the only significant predictor of diagnosis (Wilkes' lambda=0.903, p=0.003). This model correctly classified 65.9% overall into the respective DAT and VD groups. CONCLUSIONS: CDT scored according to a comprehensive technique may be of value in differentiating DAT from VD patients. We hypothesize that the classificatory ability of Freedman's method might be attributed to its presumed sensitivity to impaired executive functioning which is more pronounced in VD compared with DAT patients.