B - 142 Reason to Forget Use of (Most) Digit Span Validity Measures in Aging Clinical Samples

Abstract

Abstract Objective The Digit Span (DS) subtest has survived every iteration of the Wechsler Adult Intelligence Scale (WAIS), and the reliable digit span (RDS forward+backward) is an established embedded performance validity test (PVT). The only known DS meta-analysis drew near equivalency between the WAIS-R and WAIS-III RDS and age-corrected scaled score (ACSS) validity cutoffs, recommending use of either. The WAIS-IV included a new DS sequencing subtest. Alternate and enhanced RDS measures, adding sequencing, were derived. However, aging samples often perseverate on sequencing. The aims of this study are to confirm and update the faulty use of the enhanced RDS in the aging, establish that use of the previously recommended DS ACSS cutoff (now including sequencing) is similarly faulty, and update all DS PVT cutoff specificities in a clinical aging sample. Method Memory Clinic data were taken from 350 individuals with neuropsychologist-neurologist consensus diagnoses including 111 individuals with early Alzheimer’s disease (ad), 181 with mild cognitive impairment (MCI; 99 amnestic; 82 non-amnestic) and 58 with subjective cognitive complaints (SCC). Results Most DS embedded PVTs (e.g., ACSS<6, Enhanced RDS < 11) present with poor specificity in aging clinical populations (e.g., Χ2 (3350) = 26.331,p = <0.001), while the traditional RDS (< 6) excludes sequencing and retains the best relative specificity (81–95%), as ad performs worst on sequencing (<0.001). Conclusions While prior research favored the DS ACSS in older individuals, this study provided support for the traditional RDS in a memory clinic population. Future directions include corroborating these findings using standalone PVTs and conducting an updated DS meta-analysis.