MAPT and Alzheimer disease: The 2018 revised NIA‐AA diagnostic criteria3 have proposed the use of cortical amyloid‐beta 42 (Aβ‐42) or tau PET, cerebrospinal fluid (CSF) Aβ‐42 or phosphorylated tau, and biomarkers of neurodegeneration, including CSF T‐tau, FDG PET hypometabolism, and atrophy on MRI to identify Alzheimer's dementia (AD) in its asymptomatic stages.4