Alzheimer's & Dementia · Oct 25, 2026

Symmetric Centipolar Normalized Score (SCeNS): A standardization framework for fluid marker cross-comparability in Alzheimer's disease

By Timsina J, Chen Y, Liu M et al.

INTRODUCTION: Multiple platforms measure Alzheimer's disease fluid biomarkers, such as amyloid beta (Aβ) and p-tau, leading to heterogeneous data. Existing harmonization methods are difficult to interpret as they still provide specific cut-offs and biomarker values are not commaptible between different biomarkers. METHODS: We propose a standardization approach, Symmetric Centipolar Normalized Score (SCeNS), which uses Gaussian mixture model-derived cutoffs to rescale biomarker z-scores onto a -100 to 100 scale, with a constant cut-off to derive biomarker status, that can be applied to fluid as well as imaging biomakers. The sign (plus or minus) reflects sample's biomarker status. We present the calculation steps and demonstrate how SCeNS enables direct comparison across cohorts, platforms, and tissue types. We also demonstrate a use case of the approach using real-world data from individuals treated with lecanemab. RESULTS: SCeNS were calucated using cerebrospinal and plasma AD biomarkers measured in mutliple platforms, demostrating that the SCeNS methods provide a consistent and easy to understand biomarker level. We applied the SCeNS method to the lecanmab-treated cohort, where we demostrated the SCeNS previde easy to interpert biomkaer changes as p-tau217 showed highest unit of change, while p-tau181 had highest conversion (7.57%) to biomarker negative. DISCUSSION: SCeNS provides a simple, interpretable biomarker metric across platforms.

doi.org/10.1002/dad2.70516Open accessPubMed 42935659Biomarkers