Histograms represent the distribution of the data colored by the imaging biomarker status. The vertical black line represents the threshold derived from the first approach (a), and red lines represent the lower and upper thresholds from the second approach (b). Tau PET positivity was assessed using an in-house previously validated threshold (SUVR > 1.32). Three individuals were excluded from the histograms in d (only for visualization purposes) due to very low values of plasma %p-tau217. CSF, cerebrospinal fluid; CI, confidence interval; NPV, negative predictive value; PPV, positive predictive value; SUVR, standardized uptake value ratio.
