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This page is alzhub.org's plain-English summary of a published study, not the paper itself. It is generated from the record we hold for this study, sourced and linked below — check the original for the full text and methods.

✓ Peer-reviewed alzhub usefulness score 55 out of 100. Biomarkers

Topic: Amyloid, tau and blood-test diagnosis

Background Clinicians, researchers, and patients alike would greatly benefit from more accessible and inexpensive biomarkers for neural β-amyloid (Aβ). We aimed to assess the performance of fully automated plasma Aβ immunoassays, which correlate significantly with immunoprecipitation mass spectrometry assays, in predicting brain Aβ status as determined by visual read assessment of amyloid positron emission tomography (PET). Methods The plasma Aβ42/Aβ40 ratio was measured using a fully automated immunoassay platform (HISCL series) in two clinical studies (discovery and validation studies). The discovery and validation sample sets were retrospectively and randomly selected from participants with early Alzheimer's disease (AD) identified during screening for the elenbecestat Phase 3 program. Results We included 197 participants in the discovery study (mean [SD] age 71.1 [8.5] years; 112 females) and 200 in the validation study (age 70.8 [7.9] years; 99 females). The plasma Aβ42/Aβ40 ratio predicted amyloid PET visual read status with areas under the receiver operating characteristic curves of 0.941 (95% confidence interval [CI] 0.910-0.973) and 0.868 (95% CI 0.816-0.920) in the discovery and validation studies, respectively. In the discovery study, a cutoff value of 0.102 was determined based on maximizing the Youden Index, and the sensitivity and specificity were calculated to be 96.0% (95% CI 90.1-98.9%) and 83.5% (95% CI 74.6-90.3%), respectively. Using the same cutoff value, the sensitivity and specificity in the validation study were calculated to be 88.0% (95% CI 80.0-93.6%) and 72.0% (95% CI 62.1-80.5%), respectively. Conclusions The plasma Aβ42/Aβ40 ratio measured using the HISCL series achieved high accuracy in predicting amyloid PET status. Since our blood-based immunoassay system is less invasive and more accessible than amyloid PET and cerebrospinal fluid testing, it may contribute to the diagnosis of AD in routine clinical practice.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

Yamashita, K., Miura, M., Watanabe, S., Ishiki, K., Arimatsu, Y., Kawahira, J., et al. (2022). Fully automated and highly specific plasma β-amyloid immunoassays predict β-amyloid status defined by amyloid positron emission tomography with high accuracy. Alzheimer's research & therapy. https://doi.org/10.1186/s13195-022-01029-0

Vancouver

Yamashita K, Miura M, Watanabe S, Ishiki K, Arimatsu Y, Kawahira J, et al. Fully automated and highly specific plasma β-amyloid immunoassays predict β-amyloid status defined by amyloid positron emission tomography with high accuracy. Alzheimer's research & therapy. 2022. doi:10.1186/s13195-022-01029-0. PMID: 35739591.

BibTeX

@article{yamashita2022-35739591,
  author  = {Yamashita, K. and Miura, M. and Watanabe, S. and Ishiki, K. and Arimatsu, Y. and Kawahira, J. and Kubo, T. and Sasaki, K. and others},
  title   = {{Fully automated and highly specific plasma β-amyloid immunoassays predict β-amyloid status defined by amyloid positron emission tomography with high accuracy}},
  journal = {Alzheimer's research \& therapy},
  year    = {2022},
  doi     = {10.1186/s13195-022-01029-0},
  pmid    = {35739591},
  url     = {https://doi.org/10.1186/s13195-022-01029-0}
}

Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.

Key findings

Study details

How this study scored 55/100
How this study's score is builtJournal tier 7 of 10; Journal's citation record left out, no data; Study design 0 of 12; Strength of evidence 1 of 5; Peer-review validation 10 of 10; How recent 3 of 5; Sample size 2 of 4; Effect reported 2 of 3; Studied in people 3 of 3; Randomised / blinded 0 of 2; Times cited left out, no data; Citations per year left out, no data; Impact for its field and year left out, no data; Cited by studies here left out, no data; Still being cited left out, no data; Senior author's track record left out, no data; Institution's track record left out, no data; Multi-centre collaboration left out, no data; Indexed in PubMed 2 of 2; Free to read 2 of 2. 32 of the 58 points it could be judged on, which is 55 of 100. Total 55 of 100.32 of the 58 points we could judge = 55 of 100

Published in a peer-reviewed journal. Scored zero for study design and randomised / blinded because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 32 of the 58 points we could judge it on, which is 55 out of 100.

ComponentPointsWhy
Journal tier 7 / 10 Tier 3 — peer-reviewed journal (Alzheimer's research & therapy)
Journal's citation record — / 4 No journal record from OpenAlex — left out of this score
Study design 0 / 12 Design recorded as “clinical trial”, which our rubric does not rank (not stated in the record — scored 0)
Strength of evidence 1 / 5 Rated “low” in our summary
Peer-review validation 10 / 10 Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent 3 / 5 2022 — within 6 year(s) of the newest study here
Sample size 2 / 4 197 participants
Effect reported 2 / 3 Effect reported as a number, without an interval or test
Studied in people 3 / 3 Studied in people (participant count stated)
Randomised / blinded 0 / 2 No randomisation or blinding stated — scores zero (not stated in the record — scored 0)
Times cited — / 7 No citation count (not found in OpenAlex) — left out of this score
Citations per year — / 5 No citation count or no year — left out of this score
Impact for its field and year — / 6 No field-weighted citation impact (OpenAlex has none yet) — left out of this score
Cited by studies here — / 6 Not yet checked against this library's citation graph — left out of this score
Still being cited — / 4 No yearly citation counts — left out of this score
Senior author's track record — / 4 Senior author's record not available — left out of this score
Institution's track record — / 3 No institution listed in OpenAlex — left out of this score
Multi-centre collaboration — / 3 Institutions not listed — left out of this score
Indexed in PubMed 2 / 2 Indexed in PubMed (PMID 35739591)
Free to read 2 / 2 Free to read
Points 32 / 58 Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 32 of the 58 points we could judge it on is 55 out of 100.
Total 55 / 100 —

What each of these 20 components measures, and what this score is not →

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