In test 2 (Fig. S1D), the diagnostic performance of the PSP‐tau score and AD‐tau score showed 95.0% ± 0.02% accuracy, 87.6% ± 0.05% sensitivity, and 98.6% ± 0.02% specificity with a cutoff > 0.1986 for PSP‐RS discrimination, and 98.6% ± 0.02% accuracy, 100% sensitivity, and 100% specificity with a cutoff > 0.3431 for AD discrimination. Here, MAPT is linked to Alzheimer disease.