Comparing the accuracy of the DCTclock and Montreal Cognitive Assessment to detect cognitive impairment and cerebral amyloid status in older adults

Abstract

AbstractBackgroundSensitive and non‐invasive methods of screening for early‐stage Alzheimer’s disease (AD) are urgently needed. Digital assessment tools have the potential to improve the efficiency of cognitive screening for older adults in both clinical and research settings. The Linus Health DCTclock uses a digital pen to capture traditional clock drawing test performance and advanced analytics to evaluate the drawing process for indicators of cognitive difficulty.MethodWe compared the DCTclock to the Montreal Cognitive Assessment (MoCA), a standard cognitive screening test, in a sample of older adults (total N = 60) with normal cognition (n = 30) or a clinical diagnosis of mild cognitive impairment (MCI) or AD (n = 30) and investigated which measure is more accurate in predicting cerebral amyloid (Aβ) PET status in a subset of 32 participants with PET imaging data.ResultMoCA total score was moderately correlated with DCTclock total score (r = 0.61, p < 0.01), as well as various DCTclock composite sub‐scores. ROC analysis indicated that the MoCA had superior accuracy in differentiating between cognitively impaired and unimpaired participants (AUC = 0.98) relative to the DCTclock (AUC = 0.82). ROC analysis also indicated that the MoCA had superior accuracy in differentiating elevated versus non‐elevated Aβ PET status (AUC = 0.76) relative to the DCTclock (AUC = 0.60). A composite of the MoCA and DCTclock total scores did not improve accuracy over the MoCA alone (AUC = 0.71)ConclusionOverall, these preliminary results suggest that the MoCA is a superior cognitive screening tool and may also be useful for detecting AD associated neuropathology.