27,380 Alzheimer's and dementia studies in plain English, each scored out of 100.
We have demonstrated that three baseline measures, namely, age >or=72 years, semantic fluency less than 20 words in 90 s and inability to copy an intersecting pentagons figure, are significant predictors of dementia risk, thus validating our previous findings. 5 key findings →
Design: cross-sectional Participants: 126 Evidence: moderate
Full summary, score breakdown and related studies → Original source Full text may need a subscription
We have previously performed detailed clinical and neuropsychological assessments in a community-based cohort of patients with newly diagnosed parkinsonism, and through analysis of a subcohort with idiopathic Parkinson's disease (PD), we have demonstrated that cognitive dysfunction occurs even at the time of PD diagnosis and is heterogeneous. 1 key finding →
Design: longitudinal study Participants: 126 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
(1) outlook in PD is heterogeneous, with most dying or developing dementia or postural instability by 10 years from diagnosis, but a quarter still doing well, with preserved mobility and intact cognition; (2) death is not directly related to PD in the majority; (3) baseline clinical and genetic variables are predictive of outcome and may be helpful in selecting patients for clinical trials. 1 key finding →
Participants: 142 Evidence: moderate
Full summary, score breakdown and related studies → Original source Full text may need a subscription
The CANTAB battery was administered to a large group (n = 787) of elderly volunteers in the age range from 55 to 80 years. 4 key findings →
Participants: 787 Evidence: low
Full summary, score breakdown and related studies → Original source Full text may need a subscription
The development of novel treatments for Alzheimer's disease (AD), aimed at ameliorating symptoms and modifying disease processes, increases the need for early diagnosis. 1 key finding →
Participants: 26 Evidence: low
Full summary, score breakdown and related studies → Original source Full text may need a subscription
Groups of patients with idiopathic Parkinson's disease, multiple system atrophy, and progressive supranuclear palsy or Steele-Richardson-Olszewski syndrome, matched for overall clinical disability, were compared using three computerised cognitive tests previously shown to be sensitive to frontal lobe dysfunction. 3 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Dementia risk is associated with increased age, impaired baseline semantic fluency and the MAPT H1/H1 genotype. 3 key findings →
Evidence: moderate
Full summary, score breakdown and related studies → Original source
Research into the heterogeneous nature of cognitive impairment documented in patients with Parkinson's disease (PD) has focused on disentangling deficits that vary between individuals, evolve and respond differentially to pharmacological treatments, and relate differentially to PD dementia (PDD). 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
The organization and possible functions of basal forebrain and pontine cholinergic systems are reviewed. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
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 →