Structure and correlates of cognitive aging in a narrow age cohort.
Bottom Line: However, previous studies have typically been conducted in age-heterogeneous samples over longitudinal time lags of 6 or more years, and have failed to consider whether results are robust to a comprehensive set of controls.We fit multivariate latent difference score models to factors representing visuospatial ability, processing speed, memory, and crystallized ability.Changes were moderately interrelated, with a general factor of change accounting for 47% of the variance in changes across domains.
Affiliation: Department of Psychology.Show MeSH
Related in: MedlinePlus
Mentions: We made use of a latent difference score modeling approach (McArdle, 2009), a univariate version of which is represented as a path diagram in Figure 1. The measurement portion of this approach specifies a latent factor, y, measured by multiple tests (e.g., Ya, Yb, and Yc) on two occasions separated in time. The brackets  and  denote baseline and follow-up occasions, respectively. Each test is specified to load on the occasion-specific latent variable with a loading (λ), and each test is allowed to have an intercept (υ) and a residual variance (σ2). Cross-time residual autocorrelations (σ12) are allowed for each test. The baseline factor is set to the z-metric (M = 0, SD = 1), and the mean and the variance of the difference score can therefore be interpreted relative to this metric.