A methodology for normalizing fluid biomarker concentrations across reagent lots

Longitudinal studies of cerebrospinal fluid (CSF) and plasma biomarkers typically require the use of different assay reagent lots over time. Measured biomarker concentrations may drift from lot to lot, adding variability that may bias estimates and decrease the statistical power of biomarker analyses. Including lot as a covariate in models may not adequately adjust for lot effects, particularly if cohort characteristics change over time.