27,380 Alzheimer's and dementia studies in plain English, each scored out of 100.
Participants had a mean age of 73.4 years; 62.7% were women, and 34.9% were Hispanic or nonwhite. 5 key findings →
Design: randomized controlled trial Participants: 126 Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
Among 34 349 participants, 19 378 individuals who were free of stroke and dementia and had longitudinal BP, cognitive, and covariate data were included in the analysis. 2 key findings →
Design: longitudinal study Participants: 349 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Our findings suggest that decreasing disparities between sexes in education, due to secular increases in educational opportunities, could attenuate sex differences in dementia risk and cognitive decline in the future. 1 key finding →
Design: cohort study Participants: 924 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
In this cohort study, exposure to residential segregation throughout young adulthood was associated with worse processing speed among black participants as early as in midlife. 3 key findings →
Design: cohort study Participants: 5,115 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Study objectives Sleep duration has been associated with risk of dementia and stroke, but few studies have investigated the relationship between sleep duration and brain MRI measures, particularly in middle age. 3 key findings →
Design: prospective cohort Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
The mean age was 70.9 years (standard deviation, 5.9), 57.2% were women, 40.6% were illiterate, and 88.3% were farmers. 2 key findings →
Participants: 5,765 Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
The combinations of pathologies of Alzheimer's disease and related dementias associated with cognitive and motor decline and their onsets of associations varied; only tau tangles, Parkinson's disease pathology, and macroinfarcts were associated with decline of all three phenotypes. 5 key findings →
Design: cohort study Evidence: moderate
Full summary, score breakdown and related studies → Original source
We examined the neuropsychological test performance of a randomly selected community sample of English-speaking non-Hispanic African American and white elders in northern Manhattan. 3 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
(N = 382 at baseline) had a mean (SD) age of 75.5 (7.0) years; 61.8% were women; and 41.4% were white, 29.6% African American, 25.1% Hispanic, and 3.9% other race/ethnicity. 3 key findings →
Design: cohort study Participants: 382 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Depression is linked to an increased risk of cognitive decline and dementia; therefore, failing to diagnose and treat LLD in later life may have significant health implications. 4 key findings →
Design: longitudinal study Participants: 31,464 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
High BP accelerates gait slowing in well-functioning older adults over a long period of time, even for those who control their BP or develop hypertension later in life. 4 key findings →
Design: cohort study Participants: 2,733 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Depression and external locus of control partially mediate racial/ethnic differences in memory trajectories. 5 key findings →
Design: longitudinal study Participants: 10,173 Evidence: moderate
Full summary, score breakdown and related studies → Original source
These findings on participants who are at high risk of dropout may be useful in the planning phase of future prospective studies. 4 key findings →
Design: longitudinal study Participants: 5,278 Evidence: moderate
Full summary, score breakdown and related studies → Original source Full text may need a subscription
Although the association between high blood pressure (BP), particularly in midlife, and late-life dementia is known, less is known about variations by race and sex. 5 key findings →
Design: cohort study Participants: 2,003 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Although APOE ε4 carriers are at high risk for cognitive decline, our findings suggest possible intervention targets, including the enhancement of cognitive reserve and improvement of other psychosocial and health factors, to promote cognitive resilience among black and white APOE ε4 carriers. 5 key findings →
Design: prospective cohort Participants: 2,487 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Sample weights were used to ensure result generalizability. 5 key findings →
Design: cross-sectional Participants: 1,527 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Although, anatomical disparities of the rodent medial prefrontal cortex compared to the primate homologue are apparent, current rodent models have effectively implicated the medial prefrontal cortex as a neural substrate of cognitive decline within ageing and dementia. 4 key findings →
Design: cross-sectional Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
The objective of the study was to examine variability across multiple prospective cohort studies in level and rate of cognitive decline by race/ethnicity and years of education. 3 key findings →
Design: cohort study Participants: 4,115 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
This study demonstrates the acceptability and effectiveness of exercise on neurobehavioral function, even in older people more than 75 years of age. 1 key finding →
Design: randomized controlled trial Participants: 42 Evidence: high
Full summary, score breakdown and related studies → Original source Full text may need a subscription
These findings suggest that depressive symptoms precede memory decline, but not vice versa, in late life. 3 key findings →
Design: longitudinal study Participants: 2,425 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Non-linear associations between features of land use and cognitive impairment were confirmed in this new cohort of older people in England. 4 key findings →
Design: cross-sectional Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Late-life lower BMI relates to faster rates of decline in cognition, specifically semantic memory and episodic memory, in both blacks and whites. 2 key findings →
Design: cohort study Participants: 2,134 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Prevalent hemodialysis patients demonstrate significant cognitive decline, particularly within tests of executive function. 5 key findings →
Design: longitudinal study Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
This analysis combining data from two health systems shows that area deprivation is an independent risk factor for cognitive dysfunction in older adults. 3 key findings →
Design: cross-sectional Participants: 5,186 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Attenuation of racial inequalities in older age can be extended to cognitive outcomes, which probably reflects selective survival. 1 key finding →
Design: cross-sectional Participants: 3,875 Evidence: moderate
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 →