Plateau of practice effects and noise with repeat SDMT testing in multiple sclerosis.

ABSTRACT:

Background

The Symbol Digit Modalities Test (SDMT) is the most widely used test of cognition in people with multiple sclerosis (PwMS), and repeated testing is confounded by test-retest noise and practice effects.

Objective

To investigate the extent to which SDMT practice effects build and plateau with high-frequency testing, reliable cutoffs for longitudinal change, and whether short-interval testing improves detection of cognitive decline.

Methods

PwMS were tested with the SDMT monthly across 3 years. Plateau regression analyses were used to determine inflection points of practice effects, and the reliable-change was assessed. To evaluate effects of testing density on cognitive decline detection, this sample was compared with a separate low-density testing group.

SUBMITTER: Novakova L 

PROVIDER: S-EPMC12357967 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature