Stricker Learning Span criterion validity: a remote self-administered multi-device compatible digital word list memory measure shows similar ability to differentiate amyloid and tau PET-defined biomarker groups as in-person Auditory Verbal Learning Test

Abstract

Objective: The Stricker Learning Span (SLS) is a computer-adaptive digital word list memory test specifically designed for remote assessment and self-administration on a web-based multi-device platform (Mayo Test Drive). We aimed to establish criterion validity of the SLS by comparing its ability to differentiate biomarker-defined groups to the person-administered Auditory Verbal Learning Test (AVLT). Participants and Methods: Participants (N=353; mean age=71, SD=11; 93% cognitively unimpaired [CU]) completed the AVLT during an in-person visit, the SLS remotely (within 3 months) and had brain amyloid and tau PET scans available (within 3 years). Overlapping groups were formed for 1) those on the Alzheimer disease (AD) continuum (amyloid PET positive, A+, n=125) or not (A-, n=228), and those with biological AD (amyloid and tau PET positive, A+T+, n=55) vs no evidence of AD pathology (A-T-, n=195). Analyses were repeated among CU participants only. Results: The SLS and AVLT showed similar ability to differentiate biomarker-defined groups when comparing AUROCs (p>.05). In logistic regression models, SLS contributed significantly to predicting biomarker group beyond age, education and sex, including when limited to CU participants. Medium (A- vs A+) to large (A-T- vs A+T+) unadjusted effect sizes were observed for both SLS and AVLT. Learning and delay variables were similar in terms of ability to separate biomarker groups. Conclusions: Remotely administered SLS performed similarly to in-person-administered AVLT in its ability to separate biomarker-defined groups, providing evidence of criterion validity. Results suggest the SLS may be sensitive to detecting subtle objective cognitive decline in preclinical AD.