Primary care physicians who used a blood test measuring the ratio of two Alzheimer's-linked proteins reached 93 percent diagnostic accuracy, nearly matching the 94 percent accuracy of dementia specialists using the same test, according to findings presented at the Alzheimer's Association International Conference (AAIC) 2026. Without the blood test, primary care physicians in the study reached only 65 percent accuracy on the same patients, according to the Alzheimer's Association's release on the research. The study, led by researchers including Sebastian Palmqvist and colleagues, involved more than 1,300 patients evaluated at primary care and specialist clinics who were being assessed for cognitive symptoms; final diagnoses were confirmed against clinical follow-up and biomarker-based reference standards, per the AAIC release. The blood test measured plasma phosphorylated tau217 relative to amyloid beta 42, a ratio previously validated against PET scans and cerebrospinal fluid testing in specialist settings. This is the first large-scale test of whether that accuracy holds when the same blood result is handed to physicians outside memory clinics, the setting where most patients with cognitive complaints are first seen. Independent commentary summarized in trade coverage of the presentation, including reporting from Healio, framed the result as evidence the test could shift where accurate diagnosis happens, from specialist referral centers with long waitlists to the family doctor's office. The Alzheimer's Association's release did not describe patients being told to start or stop any treatment based on these results; the study measured diagnostic classification only.