Palmqvist S, et al. - Via two prospective, cross-sectional, multicenter studies, researchers investigated the accuracy of plasma β-amyloid (Aβ) and tau measured utilizing fully automated assays together with other blood-based biomarkers to detect cerebral Aβ. The first cohort consisted of 842 participants from the Swedish BioFINDER study and the validation cohort included 237 participants from a German biomarker study. For this investigation, plasma Aβ42, Aβ40 and tau were evaluated utilizing Elecsys immunoassays (Roche Diagnostics) and studied as predictors of Aβ status in logistic regression models in cohort 1 and replicated in cohort 2. In a validation cohort, plasma Aβ42 and Aβ40 forecast Aβ status in all stages of AD with comparable accuracy. By analyzing APOE genotype, their accuracy can be increased further. These blood tests may also be utilized in the future to prescreen Aβ positivity in clinical AD trials to reduce the costs and number of positron emission tomography scans or lumbar punctures.