Factor analyses of the ADNI neuropsychological battery: An examination of diagnostic and longitudinal invariance.

Objective: In the Alzheimer's Disease Neuroimaging Initiative (ADNI), cognitive function was tracked across multiple years by a comprehensive neuropsychological battery. In this study, we examined the latent structure of the ADNI battery and evaluated the invariance of that structure among diagnostic groups and over time.
Method: We used exploratory and confirmatory factor analyses to investigate the invariance of the ADNI battery's latent factor structure among three diagnostic groups (healthy controls, patients with mild cognitive impairment, patients with Alzheimer's disease) over a 2-year interval (baseline, 6 months, 12 months, 24 months).
Results: The results revealed a five-factor structure for the ADNI battery (memory, visuospatial processing, attention, language, executive function). This structure displayed configural invariance but not weak, strong, or strict invariance across the three diagnostic groups. Longitudinally, configural, weak, strong, and strict invariance were all established within each diagnostic group, except that strict invariance was rejected in healthy controls.
Conclusions: The ADNI battery assesses the same cognitive abilities in the three diagnostic groups, but test scores do not calibrate to these abilities equally in the respective groups, making certain statistics (e.g., factor scores) noncomparable between groups. Within each group, the latent structure and the numerical relations between individual tests and underlying factors remained invariant over 2 years, suggesting that this battery is a reliable tool for tracking longitudinal changes in specific cognitive abilities within individual diagnostic groups. (PsycInfo Database Record (c) 2021 APA, all rights reserved).