Objective: This study aimed to compare the sensitivity and specificity of a modified version of the Minnesota Cognitive Acuity Screen (MCAS-m), by adding learning and recognition memory components, to the original version MCAS to distinguish amnestic mild cognitive impairment (aMCI) from healthy controls (HCs).
Methods/design: A total of 30 individuals with aMCI and 30 HCs underwent neuropsychological testing, neurologic examination, laboratory, and brain imaging tests. Once diagnosis was confirmed, participants completed the MCAS and MCAS-m in counterbalanced order.
Results: The average administration time was 12.6 minutes for the MCAS and 13.5 minutes for the MCAS-m. Receiver operating characteristic curve analyses showed that the MCAS-m demonstrated 97% sensitivity and 97% specificity for distinguishing between aMCI and HC versus 97% and 87%, respectively, for the original MCAS in this sample.
Conclusions: Both the MCAS and the MCAS-m were highly sensitive when distinguishing between normal cognition and aMCI; however, the MCAS-m demonstrated a 10% increase in specificity compared to the original version. Improved specificity is particularly relevant to screening in larger community samples with lower base rates of MCI than clinic populations. This modified screening measure presents a brief and cost-effective tool for identifying MCI. Given the risk of progression from aMCI to Alzheimer disease dementia (AD), the MCAS-m represents a modest improvement in telephone-administered methods for the early detection of AD.
Keywords: mild cognitive impairment; screening instruments; telephone assessment.