Figure 2. Correlation of Tau Biomarkers.
Biomarkers of tau show reasonably good correlation when the lumbar puncture (LP) was performed several years prior to the PET scan (A). For individuals classified as amyloid-positive using a PET amyloid (Pittsburgh compound B) scan, correlation between CSF (phosphorylated tau [p-tau]) and flortaucipir PET was highest when the LP was performed 4–8 years prior to the PET (B). The timeframes with greatest measurement correlation for all participants (C), as well as those for participants with documented Alzheimer disease pathology (D), are shown.