Comparison of Clock Drawing Test and Rey Complex Figure Test scoring methods for detecting mild and major neurocognitive disorder due to Alzheimer's disease in a real-world clinical setting

BackgroundDirect comparisons of different scoring methods of the Clock Drawing Test (CDT) and the copy trial of the Rey Complex Figure Test (RCFT) remain limited.ObjectiveThe study aimed to compare the effectiveness of four- and two scoring systems of the CDT and the RCFT, respectively, in detecting mild neurocognitive disorder (MildND) due to Alzheimer's disease (AD) and major neurocognitive disorder (MajorND) due to AD.MethodsThe study included 141 cognitively unimpaired individuals, 209 people with MildND and 76 with MajorND due to AD. The 3-point CDT scoring method (CDT3), the Gestalt-, Freund-, and Rouleau methods were employed, while the RCFT Copy trial was scored with the 36-point Taylor system and the RCFT central-items (RCFTci) method. Statistical analyses included comparison analyses and proportional odds logistic regression (POLR) models, while stratified bootstrap resampling was used to repeatedly partition the sample into training and validation sets (70/30 ratio).ResultsThe Rouleau CDT scoring method achieved the highest classification performance (F1 = 0.67; 95% CI: 0.59-0.74), followed by the Gestalt method (F1 = 0.65; 95% CI: 0.57-0.72), the Freund method (F1 = 0.64; 95% CI: 0.56-0.72), and the CDT3 (F1 = 0.63; 95% CI: 0.55-0.71). The CDT Rouleau method and the RCFT Copy trial showed similar performance (F1 = 0.67; 95% CI: 0.59-0.74), while RCFTci was less effective (F1 = 0.62; 95% CI: 0.54-0.70).ConclusionsThe CDT and RCFT Copy trial demonstrated comparable diagnostic accuracy, yet their distinct characteristics (administration time, scoring complexity) may guide test selection across healthcare settings.