Few validated measures that assess processing speed without requiring motor response are available. The Wechsler Adult Intelligence Scale, Fifth Edition (WAIS-5) introduced Naming Speed Quantity (NSQ), a new non-motor subtest within the Processing Speed domain. Considering the prevalence of motor limitations with age and the desire to expand access, the current retrospective study aimed to evaluate the NSQ within a multidisciplinary dementia clinic with a sample of 100 adults between the ages of 70 and 85. The NSQ was evaluated within a brief battery of commonly used neuropsychological measures to assess for dementia, including RBANS, Trail Making Test, COWAT, and Animals. The results demonstrate the strongest correlation with RBANS Coding (r = .46). Although expressive language performances were also correlated with the NSQ, processing speed measures accounted for the most variance. NSQ performances were significantly lower in individuals with functional impairment (N = 43) compared to those without functional impairment (N = 57, d = .50), although the effect was larger in TMT-A (d = .95) and RBANS Coding (d = 1.02). Although the NSQ demonstrated the strongest relationship to RBANS Coding, with the WAIS-5 normative transformation, the two tests show poor agreement (ρc = .28) and low scores were infrequent.
Keywords: Dementia; WAIS-5; naming speed quantity; older adult; processing speed.