MAPT and Cognitive impairment: In conclusion, this study highlights the clinical utility of the plasma p‐tau217/Aβ42 ratio in determining cerebral amyloid and tau accumulation statuses with an overall accuracy of approximately 95% when implementing the two‐cutoff approach, which is clinically equivalent to FDA‐approved CSF tests, in patients with cognitive symptoms in clinics and in community‐based cohorts with or without cognitive impairment.