The failure to diagnose Alzheimer’s disease—the most common form of dementia in the elderly—at an early stage of molecular pathology is considered a major reason that treatments fail in clinical trials. Previous research to molecularly diagnose Alzheimer’s disease yielded “A/T/N” central biomarkers based on the measurements of proteins, β-amyloid (“A”) and tau (“T”), and “N” encompassing neurodegeneration. A/T/N can be measured in brain tissue, by in vivo brain imaging techniques, and by analysis of cerebrospinal fluid and plasma.