Abstract
Informant-based assessments of cognition and function are commonly used to differentiate individuals with amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) from those who are cognitively normal. However, determining the extent to which informant-based measures correlate to objective neuropsychological tests is important given the widespread use of neuropsychological tests in making clinical diagnoses of aMCI and AD. The aim of the current study is to determine how well the Alzheimer's Questionnaire (AQ) correlates with objective neuropsychological tests. The study utilized data from 300 individuals participating in a brain and body donation program. Individuals diagnosed with aMCI (n = 83) and AD (n = 67) were matched on age, gender, and education to a control individual (n = 150). The average age for the entire sample was 83.52±6.51 years with an average education level of 14.57±2.55 years. Results showed that the AQ correlated strongly with the Mini-Mental State Exam (r =-0.71, p < 0.001) and the Mattis Dementia Rating Scale-2 (r =-0.72, p < 0.001), and moderate correlations were noted for the AQ with memory function (Rey Auditory Verbal Learning Test Delayed Recall, r =-0.61, p < 0.001) and executive function (Trails B, r = 0.53, p < 0.001). The findings of this study suggest that the AQ correlates well with several neuropsychological tests and lend further support to the validity of the AQ as a screening instrument for cognitive impairment.