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Elecsys pT181p immunoassay: Clinical performance for ruling out amyloid pathology
Craig Ritchie, Sayuri Hortsch, Clara Quijano-Rubio, Patrick Menzel, Imke Kirste, David Caley, Anna D Burke, Christopher C Rowe et al.. Alzheimer's & dementia (Amsterdam, Netherlands), 2026-09-08
Topic: Plasma and spinal-fluid biomarkers
At a care setting-agnostic cutoff of 0.934 pg/ml, high negative predictive value (NPV) (93.8%) and acceptable positive predictive value (PPV) (46.6%) were observed against amyloid-positron emission tomography (PET). A primary care-specific cutoff of 0.722 pg/ml showed high NPV (97.9%) against amyloid-PET. Amyloid positivity prevalence for each cutoff population was 22.5% and 13.1%, respectively. The pT181p immunoassay is a high-performance test that may substantially help improve access to amyloid pathology testing for people requiring confirmation, potentially leading to timely clinical decisions and better outcomes.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
APA 7th
Ritchie, C., Hortsch, S., Quijano-Rubio, C., Menzel, P., Kirste, I., Caley, D., et al. (2026). Elecsys pT181p immunoassay: Clinical performance for ruling out amyloid pathology. Alzheimer's & dementia (Amsterdam, Netherlands). https://doi.org/10.1002/dad2.70439
Vancouver
Ritchie C, Hortsch S, Quijano-Rubio C, Menzel P, Kirste I, Caley D, et al. Elecsys pT181p immunoassay: Clinical performance for ruling out amyloid pathology. Alzheimer's & dementia (Amsterdam, Netherlands). 2026. doi:10.1002/dad2.70439. PMID: 42719535.
BibTeX
@article{ritchie2026-42719535,
author = {Ritchie, Craig and Hortsch, Sayuri and Quijano-Rubio, Clara and Menzel, Patrick and Kirste, Imke and Caley, David and Burke, Anna D and Rowe, Christopher C and others},
title = {{Elecsys pT181p immunoassay: Clinical performance for ruling out amyloid pathology}},
journal = {Alzheimer's \& dementia (Amsterdam, Netherlands)},
year = {2026},
doi = {10.1002/dad2.70439},
pmid = {42719535},
url = {https://doi.org/10.1002/dad2.70439}
}
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Key findings
- At a care setting-agnostic cutoff of 0.934 pg/ml, high negative predictive value (NPV) (93.8%) and acceptable positive predictive value (PPV) (46.6%) were observed against amyloid-positron emission tomography (PET).
- A primary care-specific cutoff of 0.722 pg/ml showed high NPV (97.9%) against amyloid-PET.
- Amyloid positivity prevalence for each cutoff population was 22.5% and 13.1%, respectively.
- The pT181p immunoassay is a high-performance test that may substantially help improve access to amyloid pathology testing for people requiring confirmation, potentially leading to timely clinical decisions and better outcomes.
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Study details
- Participants604
- Effect size93.8%; 46.6%; 97.9%
- Evidence strengthLow
How this study scored 61/100
Published in a leading specialty 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, multi-centre collaboration and free to read, so those were left out: it earned 34 of the 56 points we could judge it on, which is 61 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (Alzheimer's & dementia (Amsterdam, Netherlands)) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (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 | 5 / 5 | 2026 — within 1 year(s) of the newest study here |
| Sample size | 2 / 4 | 604 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 42719535) |
| Free to read | — / 2 | Access not recorded — left out of this score |
| Points | 34 / 56 | Scored on 10 of 20 parts. We have no data for the rest, so they are left out: 34 of the 56 points we could judge it on is 61 out of 100. |
| Total | 61 / 100 | — |
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