The Study
Diagnostic performance of plasma p-tau217 levels measured with different assays for Alzheimer’s disease
This study looked at a protein in the blood called p-tau217 and found that people with Alzheimer’s usually have more of it than people without. But it didn’t prove that the protein causes Alzheimer’s — it just shows they often go together, like how people with sunburns usually have been in the sun.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
Scientists tested three new blood tests that measure a protein called p-tau217 to see if they can tell who has Alzheimer’s disease.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 544 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1This means a simple blood draw could one day replace expensive brain scans to diagnose Alzheimer’s early — even before dementia sets in.
- 2The best two tests caught 94 out of 100 Alzheimer’s cases and never gave a false alarm (100% specific).
- 3They could even spot early signs in people with mild memory problems.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Translational Psychiatry
Year
2026
Authors
Yong He, Yurou Du, Dequan Liu, Ping Che, Yu Wang, Jia Li, Caixia Wang, Nan Zhang
Related Content
Claims (6)
Blood levels of a specific form of tau protein called p-tau217, measured using three new laboratory tests, are consistently higher in people diagnosed with Alzheimer’s dementia than in people without dementia or with other types of dementia, and these measurements can accurately identify Alzheimer’s dementia with over 92% accuracy.
Blood tests measuring p-tau217 using the DiSMS and LyMedivh™ AXL assays show higher levels in people with mild cognitive impairment from Alzheimer’s disease than in people without cognitive impairment, and these tests accurately distinguish between the two groups.
Two new blood tests for p-tau217 detect Alzheimer’s dementia with 94.4% accuracy in identifying affected individuals and 100% accuracy in identifying those without dementia, performing identically to the established ALZpath Simoa assay.
Two new blood tests for p-tau217, called DiSMS and LyMedivh™ AXL, produce results that match the established ALZpath Simoa assay with high consistency, showing they measure the same protein marker in blood.
Blood levels of p-tau217 can identify the presence of amyloid-beta plaques in the brain with 95% to 97% accuracy, allowing Alzheimer's pathology to be detected decades before symptoms appear.
In people with Alzheimer’s dementia or mild cognitive impairment, the amount of p-tau217 in the blood does not change with how well they perform on memory and thinking tests.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.