The mean scores shown in Table 2 indicate that participants in the AD group performed more poorly than those in the control group across all composite domains. In hierarchical regression analyses, after controlling for lifetime tobacco and other substance use, education, age, and language of test administration, AD group status was associated with poorer performance in the domains of Verbal Story Memory (β = −31, p = .041), Self-Monitoring (β = .28, p = .045), and Psychomotor Speed and Coordination (β = .34; p = .03) (see Table 3). In these domains, alcohol use, other substance use, and the listed demographic variables together account for 26% to 38% of the variability in performance. Poorer performance in these domains suggests poorer recall rates on story memory tasks; a tendency to commit more repetition, intrusion, and rule-violation errors across various tests; and slower completion times on motor tasks. AD group status was not statistically significantly associated with performance in the domains of Verbal List Learning, Planning and Problem-Solving, Attention and Concentration, Sequencing Ability, Expressive Language, Visuospatial Construction, and Visual Memory.
