Adaptive Functioning Among Older Adults: The Essence of Information Processing Speed in Executive Functioning

Abstract Objective The current study investigated the degree to which information processing speed mediates the association between executive functioning and adaptive functioning among older adults. Method Cases (N = 239) were selected from a clinical database of neuropsychological evaluations. Inclusion criteria were age 60+ (M = 74.0, standard deviation = 6.9) and completion of relevant study measures. Participants were majority White (93%) women (53.1%). The Texas Functional Living Scale was used as a performance-based measure of adaptive functioning. Information processing speed was measured using the Coding subtest from the Repeatable Battery for the Assessment of Neuropsychological Status. Executive functioning performance was quantified using part B of the Trail Making Test, Controlled Oral Word Association Test, and Similarities and Matrix Reasoning subtests from the Wechsler Abbreviated Scale of Intelligence, second edition. Mediation models were assessed with bootstrapped confidence intervals. Results Information processing speed mediated all measures of executive functioning. Direct effects were significant for all models (ps