27,380 Alzheimer's and dementia studies in plain English, each scored out of 100.
Cognitive decline is a debilitating manifestation of disease progression in Parkinson's disease. 4 key findings →
Design: longitudinal study Participants: 3,200 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
At baseline measurements, amyloid burden does not distinguish between cognitively impaired and unimpaired subjects with PD without dementia, but our data suggest that amyloid contributes to cognitive, but not motor, decline over time. 3 key findings →
Design: cohort study Participants: 46 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Higher amyloid beta burden was associated with increasing anxious-depressive symptoms over time in cognitively normal older individuals. 4 key findings →
Design: longitudinal study Participants: 270 Evidence: moderate
Full summary, score breakdown and related studies → Original source
In our training set, people with Parkinson's disease, multiple system atrophy, and dementia with Lewy bodies had lower CSF α-synuclein concentrations than patients with Alzheimer's disease and other neurological disorders. 1 key finding →
Design: cross-sectional Evidence: moderate
Full summary, score breakdown and related studies → Original source Full text may need a subscription
This relationship was evident even after accounting for degree of memory deficit across the continuum of cognitive impairment and dementia. 2 key findings →
Participants: 793 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Global cortical amyloid burden is high in dementia with Lewy bodies (DLB) but low in Parkinson disease dementia. 3 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
From a total sample of 559 older adults from the Massachusetts Alzheimer's Disease Research Center longitudinal cohort, 454 were included in the primary analysis: 283 with clinically normal cognition (CN), 115 with mild cognitive impairment (MCI), and 56 with subjective cognitive concerns (SCC) but no objective impairment, a proposed transitional group between CN and MCI. 1 key finding →
Design: longitudinal study Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Cross-sectional and longitudinal studies. 4 key findings →
Design: cross-sectional Participants: 413 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Twenty-four patients with Lewy body disease (7 DLB, 8 PD-impaired, and 9 PD-normal) underwent multimodal brain imaging, cognitive testing, and neurologic evaluation, and imaging measures were compared with those of an independently acquired group of 29 controls with minimal brain amyloid burden as measured with carbon 11-labeled Pittsburgh Compound B ([11C]PiB) positron emission tomography (PET). 5 key findings →
Design: cross-sectional Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
Amyloid deposition is associated with lower cognitive performance both in AD patients and in the normal elderly, but the association is modified by CR, suggesting that CR may be protective against amyloid-related cognitive impairment. 4 key findings →
Participants: 17 Evidence: low
Full summary, score breakdown and related studies → Original source
Future longitudinal studies examining the association of more severe depressive symptoms and cerebral tau accumulation are needed to substantiate this finding and to guide prevention and treatment in AD. 4 key findings →
Design: cross-sectional Evidence: moderate
Full summary, score breakdown and related studies → Original source
These results suggest that increased baseline hallucinations, apathy and anxiety are associated with current and future disease progression in AD. 3 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
Plasma Abeta measures increase with age, but, in contrast to reports on familial AD, plasma Abeta measures were neither sensitive nor specific for the clinical diagnosis of mild cognitive impairment or sporadic AD. 2 key findings →
Participants: 146 Evidence: low
Full summary, score breakdown and related studies → Original source
Impairment in instrumental activities of daily living (IADL) heralds the transition from mild cognitive impairment (MCI) to dementia and is a major source of burden for both the patient and caregiver. 4 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
Free full text links and the Full text may need a subscription label come from Unpaywall, Europe PMC and OpenAlex records of free copies, checked 10 Oct 2026. A study with neither is unknown, not paywalled. Show only studies that are free to read
This is alzhub's own score. It is not an official metric, not an impact factor, and no journal, publisher or ranking body endorses it. We built it so that a reader who is not a scientist can tell a landmark trial from a conference abstract without having to already know the difference. Every point comes from one of 20 components, all of them printed on the study itself, so you can disagree with our arithmetic rather than having to trust the total.
Journals are placed in ordered tiers, never given a numeric impact factor — we could not verify current impact factors from a source we control, and an invented one would be worse than none. Tier 1 is the top-tier general journals (NEJM, The Lancet, JAMA, Nature, Science, Nature Medicine); tier 2 is the leading specialty journals; tier 3 is every other peer-reviewed journal. A separate part scores how much the journal's own papers are cited, which tells the tier-3 journals apart.
Two rules we don't bend. First, we never fill in a missing value: if a record does not state a sample size or a design, that component scores zero, and if we simply have no data for a part, such as a citation count, that part is left out and the study is scored on the parts we could check. The study card says which. Second, anything that is not a peer-reviewed article is capped at 16/100 and carries a warning chip — so a conference abstract or a company press release can never outrank a peer-reviewed paper, no matter how good it looks.
We rank a rigorous null result — a good trial showing that something does not work — above an early positive finding. Someone deciding whether to buy a supplement is served by that, and the rigour is already counted by the design and journal components.
The score is computed from the published data alone and is reproducible: the same file always yields the same numbers.
See the whole rubric drawn out → — four charts covering all 27,380 studies: how the scores are spread and where the cap bites, which of the 20 components the library is strong and weak on, which subjects rest on stronger evidence, and what kinds of study each subject is actually built from.
This is a large sample of the Alzheimer's literature, not an exhaustive index of it. It holds 27,380 records, built mostly from automated pulls of Europe PMC (60.6% of the library) and OpenAlex (18.6%), plus smaller pulls from PubMed, Crossref and medRxiv. If a study, a drug, or a finding isn't here, that is not evidence it doesn't exist in the literature — it may simply not have been pulled in yet.
1,032 records (3.8% of the library) are not peer-reviewed — 962 of those are preprints posted before any journal review, and the rest are conference abstracts, regulatory notices and reports. Every study card on this page states its status plainly, and the score above is capped for anything that isn't a peer-reviewed article.
See the full, machine-readable breakdown of this library's coverage →