Effects of cognitive speed of processing training on a composite neuropsychological outcome: Results at one-year from the IHAMS randomized controlled trial

Abstract

Background: Age-related cognitive decline is common and well-documented. Cognitive speed of processing training (SOPT) has been shown to improve trained abilities (Useful Field of View; UFOV), but transfer to individual non-trained cognitive outcomes or neuropsychological composites is sparse. We examine the effects of SOPT on a composite of six equally weighted tests - UFOV, Trail-making A and B, Symbol Digit Modality, Controlled Oral Word Association, Stroop Color and Word, and Digit Vigilance. Methods: 681 patients were randomized separately within two age-bands (50-64, ≥ 65) to three SOPT groups (10 initial hours on-site, 10 initial hours on-site plus 4 hours of boosters, or 10 initial hours at-home) or an attention-control group (10 initial hours on-site of crossword puzzles). At one-year, 587 patients (86.2%) had complete data. A repeated measures linear mixed model was used. Results: Factor analysis revealed a simple unidimensional structure with Cronbach's α of 0.82. The time effect was statistically significant ( p < 0.001; ηp2 = 0.246), but the time by treatment group ( p = 0.331), time by age-band ( p = 0.463), and time by treatment group by age-band ( p = 0.564) effects were not. Conclusion: Compared to the attention-control group who played a computerized crossword puzzle game, assignment to 10-14 hours of SOPT did not significantly improve a composite measure of cognitive abilities.