ACE clock scoring: a comparison with eight standard correction methods in a population of low educational level

The authors compared the accuracy of Addenbrooke's Cognitive Examination Clock Drawing Test scoring method with 8 standard Clock Drawing Test scoring methods in a Spanish speaking population of low educational level. A clinical group composed of 70 patients affected by dementia and 25 patients with memory complaints without dementia was compared with 72 controls matched for gender, age, and educational level. The clinical group was studied with standard neuropsychological instruments and neuroimaging. Clock Drawing Tests extracted from Addenbrooke's Cognitive Examination were randomly distributed and scored by 2 independent raters. There were statistically significant differences between the different scoring methods. Addenbrooke's Cognitive Examination Clock Drawing Test scoring method obtained and optimal areas under the curve and interrater reliability, showing no statistical differences with previously standardized systems. In our population, Addenbrooke's Cognitive Examination and the methods of Cahn, Mendez, Rouleau, Shulman, and Sunderland were of optimal and equivalent usefulness regarding dementia detection.