Capillary blood sampling from the finger allows detection of Alzheimer's disease biomarkers p-tau217, NfL and GFAP, which correlate strongly with venous blood measurements.[1][2][4] These tests do not require strict temperature control or immediate sample centrifugation.[1] Capillary p-tau217 accurately classifies amyloid burden and achieves 86% accuracy in identifying Alzheimer's disease-related changes compared to spinal fluid.[4] The study included 337 participants from 7 centers, of whom 304 provided matched capillary and venous blood samples.[2][4] The integration of blood biomarkers increases the diagnostic accuracy of primary care physicians from approximately 61% to 91%.[1] The method supports remote assessment in epidemiology to estimate the prevalence of Alzheimer's disease and enroll in clinical trials. The tests are also effective in persons with Down syndrome and allow self-sampling with high compliance.[2]