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Home › Research › What the research found › Every row

Every row of the evidence table

One row per finding: what was tested, which way the result went, and how the study was built. The answer by area, and where the studies disagree, are on the main page.

Every row

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Area All 382 Care, carers and services 140 Medicines 85 Genes (not modifiable) 35 All modifiable factors together 27 Diet and supplements 23 Exercise and activity 21 Sleep, mood and social life 19 Hearing and vision 8 Alcohol, tobacco and cannabis 6 Infection and vaccination 5 Heart and metabolic health 4 Injury, delirium and falls 4 Environment 3 Cognitive activity 2
Question Both Prevention 190 Treatment 192
Direction Any Benefit 144 Harm 105 No effect 38 Mixed 37 No direction reported 58
Design Any meta-analysis 57 randomised trial 44 phase 3 trial 15 systematic review 9 phase 2 trial 10 cohort study 136 phase 1 trial 2 cross-sectional study 31 case-control study 14 modelling study 20 regulatory decision 7 company announcement 1 coverage determination 1 None 35
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Showing 1 of 382 rows. One row per study per exposure: a study that tested two different things appears twice, once for each.

Scroll the table sideways to see every column.

Research and outcomes, 1 row. Every row links to its source.
Exposure Question Direction Outcome measured Design People Effect size, as the source reported it Source
Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services Prevention Benefit
why

Direction is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. Stand-alone plasma p-tau217 gave 81% accuracy and 79% PPV; confirming positives with PET or CSF raised both to 91% while cutting PET scans needed to find 100 amyloid-positive people from 536 to 124. Immunoassays matched mass spectrometry on PPV but had lower accuracy.

 Accuracy and positive predictive value for amyloid positivity (CSF or PET) in cognitively unimpaired people, stand-alone and in a two-step workflow cross-sectional study 2,916 As a stand-alone test, plasma p-tau217 achieved a positive predictive value (PPV) of 79% (95% CI, 74-84) and an overall accuracy of 81% (95% CI, 80-82). In a 2-step workflow, the PPV and accuracy significantly increased to 91% (95% CI, 86-95). While this approach required screening of 677 individuals with plasma p-tau217 to identify 100 Aβ-positive individuals, compared to 536 participants when using PET alone, it reduced the need for PET testing to 124 JAMA Neurology 2025
✓ Peer-reviewed PMID 40952756

How this table was built, and where it is weak →