Evaluation of different ways to identify persistent positivity of lupus anticoagulant in systemic lupus erythematosus
Open accessAbstract
Objective: Persistent positivity for lupus anticoagulant has been associated with an increased risk of thrombosis among patients with SLE. Persistent positivity is often defined as having two positive assessments separated by more than 90 days. Our objective was to determine whether frequent repeated lupus anticoagulant testing would identify more patients with persistent positivity, and whether the additional patients identified were still at increased risk of thrombosis. Methods: Using a large longitudinal cohort with frequent lupus anticoagulant testing, we compared three different hypothetical clinical strategies for identifying persistent positivity: (1) assessment of lupus anticoagulant twice more than 90 days apart; (2) assessment of lupus anticoagulant annually, with repeat testing if an annual assessment was positive; and (3) assessment of lupus anticoagulant 16 times (approximately quarterly for 4 years). The prevalence of persistent positivity was compared between the approaches and by demographic subgroups. Subgroups based on these definitions were compared with respect to the risk of thrombosis in subsequent follow-up using discrete survival analysis. Results: Among the 785 patients included in our analysis, the prevalence of persistent lupus anticoagulant as defined by the first two patient assessments was 4.3%. Annual assessment resulted in a prevalence of 6.6%, and using all 16 assessments resulted in a prevalence of 10.5%. The prevalence was substantially higher in men than in women, and in Caucasians than in African-Americans (p<0.01 for all comparisons). The rate of thrombosis was significantly elevated among those with persistently positive lupus anticoagulant by any definition (HR ranging from 2.75 to 3.42) relative to those without persistently positive lupus anticoagulant. Conclusion: While there are other risk factors for thrombosis (including other antiphospholipid subtypes), more frequent testing (not limited to twice over 3 months) for lupus anticoagulant would be useful for identifying more patients with SLE at elevated risk for thrombosis.
AI snapshot
Written from the paper’s full text.
TL;DR
In 785 patients with SLE from the Hopkins Lupus Cohort, more frequent lupus anticoagulant testing identified more persistent positivity: prevalence rose from 4.3% with the first two assessments to 6.6% with annual assessment and 10.5% with 16 assessments. Patients persistently positive by any definition had elevated subsequent thrombosis risk, with adjusted rate ratios of 2.75–3.42.
Key findings
- Persistent lupus anticoagulant prevalence was 4.3% (95% CI 2.9 to 5.7) using the first two assessments separated by >90 days, 6.6% (4.8 to 8.3) using annual assessment with reassessment of positives, and 10.5% (8.3 to 12.7) using any two or more positives among 16 assessments.
- Prevalence was substantially higher in men than women and in Caucasians than African-Americans; for example, with 16 assessments, prevalence was 20.7% in men vs 9.7% in women and 12.2% in Caucasians vs 8.6% in African-Americans.
- Over 5411 person-years after the first 16 assessments, 91 thrombotic events occurred in 80 patients. Persistent positivity by any definition was associated with higher thrombosis rates: adjusted rate ratios were 3.42 (first two assessments), 3.08 (annual assessments), and 2.75 (16 assessments).
- Alternative measures also predicted thrombosis: having ≥50% of the first 16 assessments positive had an adjusted rate ratio of 3.86, and mean dRVVT ≥45 s had an adjusted rate ratio of 4.14.
Methods
- Longitudinal analysis within the Hopkins Lupus Cohort, including 785 patients with SLE who had at least 16 lupus anticoagulant assessments after 2003, excluding visits on anticoagulation.
- Lupus anticoagulant was assessed by dilute Russell viper venom time (dRVVT) at every cohort visit; for dRVVT ≥45 s, mixing and confirmatory tests were performed, and missing confirmatory results in 20% of elevated dRVVT cases were imputed using multiple imputation.
- Three hypothetical strategies for persistent positivity were compared for prevalence and demographic differences; thrombosis after the first 16 assessments was analyzed using discrete survival analysis with generalized estimating equations, adjusted for age, race, and sex.
Limitations
- Stated: the study was carried out at a single clinical centre, so findings may mainly apply to similar Caucasian and African-American patients with SLE seen in Baltimore, Maryland; because it was a real-world cohort, the time span needed to accrue 16 assessments varied.
- Evident: the testing strategies are hypothetical and based on observational cohort data, 20% of elevated dRVVT confirmatory tests were missing and imputed, and the cohort was predominantly female (93%) with limited racial/ethnic categories, which may limit generalizability.
Model-written summary. Check it against the paper before relying on it.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
6 of 15 cited sources checked · 5 supported · 0 flagged · accuracy not yet measured
- Interpretationcitation
This finding contrasts with Erkan et al, who found that more than three-quarters of subsequent tests of lupus anticoagulant were consistent with baseline test results, regardless of the laboratory.
“This contrasts with the results of Erkan et al,13 who found that more than three-quarters of subsequent tests of lupus anticoagulant were consistent with baseline test results, regardless of the laboratory.”
Quote in the paperSubstantial claim1 of 1 sources checked- cites [13] source
- Findingown data
Among the 785 patients included, the prevalence of persistent lupus anticoagulant as defined by the first two assessments was 4.3%.
“Among the 785 patients included in our analysis, the prevalence of persistent lupus anticoagulant as defined by the first two patient assessments was 4.3%.”
- Also stated in: § Definitions of persistent positivity · plain
“It can be seen that if only the first two lupus anticoagulant assessments are used, 4.3% of the patients were identified as being persistently positive.”
Quote in the paperSubstantial claim - Also stated in: § Definitions of persistent positivity · plain
- Findingown data
Similar findings were observed when the analysis was based on 12 or 20 lupus anticoagulant assessments.
“Similar findings were observed when we based the analysis on 12 or 20 lupus anticoagulant assessments (online supplemental table S2).”
Quote in the paperSubstantial claim - Findingown data
The patients were followed for a total of 5411 person-years after their first 16 lupus anticoagulant assessments.
“The patients in this analysis were followed for a total of 5411 person-years after their first 16 lupus anticoagulant assessments.”
Quote in the paperNot a substantial claim - Findingown data
Of the remaining 19.6%, most were positive at less than 6 of the 16 assessments.
“Of the remaining 19.6%, most were positive at less than 6 of the 16 assessments.”
Quote in the paperNot a substantial claim
- Findingown data
There were a small number of patients (2.9%) positive at more than 75% of their assessments.
“There were a small number of patients (2.9%) positive at more than 75% of their assessments.”
Quote in the paperNot a substantial claim - Findingown data
Using all 16 assessments resulted in a prevalence of persistent lupus anticoagulant of 10.5%.
“using all 16 assessments resulted in a prevalence of 10.5%.”
- Also stated in: § Definitions of persistent positivity · plain
“Finally, more than double the number (10.5%) of patients were defined as being persistently positive if all 16 lupus anticoagulant assessments were considered.”
Quote in the paperSubstantial claim - Also stated in: § Definitions of persistent positivity · plain
- Findingown data
Of the patients, 80.4% were negative at all 16 assessments.
“Of the patients, 80.4% were negative at all 16 assessments.”
Quote in the paperSubstantial claim - Findingown data
The prevalence of persistent lupus anticoagulant was substantially higher in Caucasians than in African-Americans, by 1.4-3.8 times depending on the definition.
“The prevalence was substantially higher in men than in women, and in Caucasians than in African-Americans (p<0.01 for all comparisons).”
- Also stated in: § Definitions of persistent positivity · boosted
“There was a strikingly higher prevalence of persistent positivity for men (vs women) and for Caucasians (vs African-Americans).”
- Also stated in: § Discussion · plain
“Depending on the definition, the prevalence of persistent lupus anticoagulant was 1.4–3.8 times higher in Caucasians than in African-American patients with SLE.”
Quote in the paperNot a substantial claim - Also stated in: § Definitions of persistent positivity · boosted
- Findingown data
The rate of thrombosis was significantly elevated among those with persistently positive lupus anticoagulant by any definition (HR ranging from 2.75 to 3.42) relative to those without persistently positive lupus anticoagulant.
“The rate of thrombosis was significantly elevated among those with persistently positive lupus anticoagulant by any definition (HR ranging from 2.75 to 3.42) relative to those without persistently positive lupus anticoagulant.”
- Also stated in: § Assessment of thrombotic risk · plain
“It can be seen that for all three definitions, those with persistent positivity had a higher rate of thrombosis.”
Quote in the paperSubstantial claim - Also stated in: § Assessment of thrombotic risk · plain
- Findingown data
During follow-up, 91 thrombotic events were experienced by 80 patients.
“During that follow-up, 91 thrombotic events were experienced by 80 patients.”
Quote in the paperNot a substantial claim - Findingown data
More than twice as many high-risk patients were identified using the broader definition (any two positives in the first 16 assessments) compared with the first two assessments.
“Given the fact that more than twice as many high-risk patients were identified using the former strategy, this suggests that clinicians should test for lupus anticoagulant more frequently and allow for a wider definition of persistent positivity.”
Quote in the paperSubstantial claim - Findingown data
The rate of thrombosis was similar irrespective of the way persistent positivity was identified.
“The rate of thrombosis was similar irrespective of the way persistent positivity was identified.”
- Also stated in: § Discussion · plain
“A third surprise was that the association between persistently positive lupus anticoagulant and thrombosis was similar, irrespective of how persistent positivity was defined.”
Quote in the paperSubstantial claim - Also stated in: § Discussion · plain
- Findingown data
The average value (in seconds) of dRVVT time served as an equally strong predictor of future risk of thrombosis as did persistent positivity based on mixing and confirmatory tests.
“We found that the average value (in seconds) of dRVVT time served as an equally strong predictor of future risk of thrombosis as did persistent positivity based on mixing and confirmatory tests.”
Quote in the paperSubstantial claim - Findingown data
There is a trend such that the more frequently one is positive, the greater the risk of thrombosis.
“As seen in table 4, there is a trend such that the more frequently one is positive, the greater the risk of thrombosis.”
Quote in the paperSubstantial claim - Findingown data
Similar gradients of increased percentages defined as persistently positive were seen if classification was based on 12 or 20 assessments.
“Similar gradients of increased percentages defined as persistently positive were seen if we based the classification on 12 or 20 assessments (online supplemental table S1).”
Quote in the paperNot a substantial claim - Findingown data
Those with the highest mean dRVVT had the highest risk of thrombosis.
“As seen in table 4, those with the highest mean dRVVT had the highest risk of thrombosis.”
Quote in the paperSubstantial claim - Findingown data
The prevalence of persistent lupus anticoagulant was substantially higher in men than in women, by 2-3.3 times depending on the definition.
“The prevalence was substantially higher in men than in women, and in Caucasians than in African-Americans (p<0.01 for all comparisons).”
- Also stated in: § Definitions of persistent positivity · boosted
“There was a strikingly higher prevalence of persistent positivity for men (vs women) and for Caucasians (vs African-Americans).”
- Also stated in: § Discussion · plain
“Depending on the definition, the prevalence of persistent lupus anticoagulant was 2–3.3 times higher in men than in women.”
Quote in the paperNot a substantial claim - Also stated in: § Definitions of persistent positivity · boosted
- Findingown data
The elevated rate ratios for those with persistent positivity were even higher after adjustment for age, race and sex.
“The elevated rate ratios for those with persistent positivity were even higher after adjustment for age, race and sex.”
Quote in the paperNot a substantial claim - Findingown data
Annual assessment resulted in a prevalence of persistent lupus anticoagulant of 6.6%.
“Annual assessment resulted in a prevalence of 6.6%”
- Also stated in: § Definitions of persistent positivity · plain
“Additional patients were identified as being persistently positive if an assessment was made annually (6.6%).”
Quote in the paperSubstantial claim - Also stated in: § Definitions of persistent positivity · plain
- Findingown data
These events consisted of 52 arterial thromboses, 36 venous thromboses and 3 classified as both.
“These consisted of 52 arterial thromboses, 36 venous thromboses and 3 classified as both.”
Quote in the paperNot a substantial claim - Findingown data
Among those ever positive for lupus anticoagulant, the majority of patients with SLE were positive on 25% or less of their visits.
“First, we found that, among those who were ever positive for lupus anticoagulant, the majority of patients with SLE were positive on 25% or less of their visits.”
Quote in the paperSubstantial claim - Findingown data
The prevalence of persistent positivity among patients with SLE differed strikingly by patient demographics.
“The second surprise was that the prevalence of persistent positivity among patients with SLE differed strikingly by patient demographics.”
Quote in the paperNot a substantial claim - Interpretationcitation
The finding of higher prevalence of persistent lupus anticoagulant in men is consistent with the LUMINA cohort.
“This finding is consistent with the findings from the Lupus in Minorities: Nature versus Nurture (LUMINA) cohort.16”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [16] source
- Interpretationown data
Frequent testing (not limited to twice over 3 months) for lupus anticoagulant would identify more patients with SLE at increased risk for thrombosis.
“Frequent testing (not limited to twice over 3 months) for lupus anticoagulant would identify more patients with SLE at increased risk for thrombosis.”
- Also stated in: § Conclusion · hedged
“While there are other risk factors for thrombosis (including other antiphospholipid subtypes), more frequent testing (not limited to twice over 3 months) for lupus anticoagulant would be useful for identifying more patients with SLE at elevated risk for thrombosis.”
Quote in the paperSubstantial claim - Also stated in: § Conclusion · hedged
- Interpretationown data
Due to the sporadic nature of lupus anticoagulant, different strategies for defining and testing for persistent positivity result in different determinations of prevalence.
“Due to the sporadic nature of lupus anticoagulant, different strategies for defining and testing for persistent positivity result in different determinations of prevalence.”
Quote in the paperSubstantial claim - Interpretationown data
Gradations in the classic three-part definition of lupus anticoagulant confer risk.
“Thus, gradations in the classic three-part definition of lupus anticoagulant confer risk.”
Quote in the paperSubstantial claim - Interpretationreasoning
The findings may mainly apply to patients similar to the Caucasian and African-American patients with SLE seen in Baltimore, Maryland.
“Thus, the findings may mainly apply to patients similar to the Caucasian and African-American patients with SLE seen in Baltimore, Maryland.”
Quote in the paperNot a substantial claim - Premisecitation
The antiphospholipid score found that the initial screen was a risk factor, not just the confirmatory test.
“The antiphospholipid score also found that the initial screen was a risk factor (not just the confirmatory test).17”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [17] source
- Classified as probably not a substantial claim. 14
- May combine two claims. 1
Classified as probably not a substantial claim.
PremisecitationThe positive predictive value of the Sapporo criteria for classification of 'true' antiphospholipid syndrome may be higher than the Sydney criteria.
“The positive predictive value of the Sapporo criteria for classification of ‘true’ antiphospholipid syndrome may be higher than the Sydney criteria.9”
Quote in the paperSubstantial claim1 of 1 sources checked- cites [9] Park, 2016, Clinical application of revised laboratory classification criteria for antiphospholipid antibody syndrome: is the follow-up interval of 12 weeks instead of 6 weeks significantly useful?, Biomed Res Int source
Classified as probably not a substantial claim.
PremisecitationThe Sydney criteria (2006) defined persistent positivity as two or more positive findings separated by at least 12 weeks.
“The definition in the Sydney criteria (2006) was changed to 12 weeks.1”
Quote in the paperSubstantial claim1 of 1 sources checked- cites [1] source
Probably not a substantial claim: may not pass S3 (load-bearing).
Study design and conductcitationSLE was diagnosed and classified based on either the revised American College of Rheumatology or the Systemic Lupus International Collaborating Clinics classification criteria.
“SLE was diagnosed and classified based on either the revised American College of Rheumatology10 or the Systemic Lupus International Collaborating Clinics classification criteria.11”
Quote in the paperNot a substantial claim1 of 2 sources checkedClassified as probably not a substantial claim.
PremisecitationThe definition of persistent positivity has varied in different iterations of classification criteria for antiphospholipid syndrome.
“The definition of ‘persistent positivity’ has varied in different iterations of classification criteria for antiphospholipid syndrome and has never been based on evidence.”
Quote in the paperSubstantial claim1 of 2 sources checked- Rests on an assumption: The definition of persistent positivity has never been based on evidence.
Classified as probably not a substantial claim.
PremisecitationPatients with antiphospholipid antibodies are at increased risk of thrombosis or adverse pregnancy outcomes.
“Patients with antiphospholipid antibodies (lupus anticoagulant, anticardiolipin and anti-beta 2 glycoprotein) are at increased risk of thrombosis or adverse pregnancy outcomes.1”
Quote in the paperSubstantial claim1 of 1 sources checked- cites [1] source
The ‘Update of the classification criteria’ section associates medium- or high-titer anticardiolipin antibodies with clinical manifestations of APS and reports that multiple antibody positivity increases thrombosis rates. Table 2 pairs persistent positivity for the named antibodies with thrombosis or pregnancy morbidity as APS criteria. The citing sentence omits those titer and persistence qualifications, so the paper does not establish increased risk for every patient with a positive antibody test. (LLM, conf=0.83)
Experimental — accuracy not yet measured
Probably not a substantial claim: may not pass S3 (load-bearing).
Findingown dataFor 89% of the patients, the first 16 assessments took place over a time period of 3 years or more.
“For 89% of the patients, the first 16 assessments took place over a time period of 3 years or more.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationEven in the absence of antiphospholipid antibodies, patients with SLE have an increased risk of thromboembolic events.
“Even in the absence of antiphospholipid antibodies, patients with SLE have an increased risk of thromboembolic events.3”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [3] Long, 1991, The relationship of antiphospholipid antibodies to thromboembolic disease in systemic lupus erythematosus: a cross-sectional study, Thromb Haemost source
Classified as probably not a substantial claim.
Study design and conductown dataMissing confirmatory test values for 20% of patients with elevated dRVVT were imputed using multiple imputation based largely on the degree of elevation of dRVVT.
“These values were imputed using multiple imputation, based largely on the degree of elevation of dRVVT.”
Quote in the paperSubstantial claimMay combine two claims.
PremisecitationLupus anticoagulant has a much stronger correlation with thrombosis and pregnancy morbidities in SLE than other antiphospholipid antibodies.
“Lupus anticoagulant has a much stronger correlation with thrombosis2 3 and pregnancy morbidities4 5 in SLE.”
Quote in the paperSubstantial claim0 of 2 sources checked- cites 2 3
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- cites 4 5
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Classified as probably not a substantial claim.
Study design and conductown dataStatistical inference was based on generalised estimating equations to account for the fact that some patients experienced more than one thrombosis.
“Statistical inference was based on generalised estimating equations to account for the fact that some patients experienced more than one thrombosis.”
Quote in the paperSubstantial claimClassified as probably not a substantial claim.
PremisecitationThe Sapporo criteria (1999) defined persistent positivity as two or more positive findings separated by at least 6 weeks.
“The Sapporo criteria (1999) defined persistent positivity as two or more positive findings separated by at least 6 weeks.6”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [6] source
Classified as probably not a substantial claim.
PremisecitationThe association with thrombosis is much stronger with persistent antiphospholipid positivity than with transient positivity.
“Although there is an association with transient antiphospholipid positivity, the association is thought to be much stronger with persistent positivity.3 5”
Quote in the paperSubstantial claim0 of 1 sources checked- cites 3 5
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Classified as probably not a substantial claim.
Premisenone givenThe likelihood of identifying a patient with persistent positivity based on the definition depends on the frequency with which lupus anticoagulant is assessed.
“The likelihood of identifying a patient with persistent positivity based on this definition clearly depends on the frequency with which it is assessed.”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
Study design and conductreasoningDue to the study being performed in a real-world clinical cohort, there was some variation in the span of time needed to accrue 16 lupus anticoagulant assessments.
“Due to the fact that the study was performed in a real-world clinical cohort, there was some variation in the span of time needed to accrue 16 lupus anticoagulant assessments.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
Study design and conductnone givenThe study was carried out at a single clinical centre.
“However, one limitation of this study is that it was carried out at a single clinical centre.”
Quote in the paperNot a substantial claim
The paper relies on this without support.
The definition of persistent positivity has never been based on evidence.
“The definition of ‘persistent positivity’ has varied in different iterations of classification criteria for antiphospholipid syndrome and has never been based on evidence.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the authors' experience, aPL titres in SLE patients can fluctuate over time and contribute risk even at low and moderate titres.
“In our experience, aPL titres in SLE patients can fluctuate over time and contribute risk even at low and moderate titres [22].”
From Antiphospholipid patterns predict risk of thrombosis in systemic lupus erythematosus (2021) · cites this paper as [22]
The Discussion (page unavailable) reports that lupus anticoagulant positivity in patients with SLE was sporadic across visits, supporting fluctuation over time. It also says gradations in lupus anticoagulant testing confer thrombotic risk, but the paper does not establish that low or moderate aPL titres confer risk; its analysis concerns lupus anticoagulant test results rather than aPL titre categories. (LLM, conf=0.84)
Experimental — accuracy not yet measured
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Abstract claims p<0.01 for all demographic comparisons
MajorThe abstract says all sex and race comparisons have p<0.01, but Table 3 reports p-values ranging from 0.021 to 0.12 for five of the six comparisons.
“The prevalence was substantially higher in men than in women, and in Caucasians than in African-Americans (p<0.01 for all comparisons).”
“Note: *P=0.051 comparing men with women. †P=0.0011 comparing African-Americans with Caucasians. ‡P=0.021 comparing men with women. §P=0.038 comparing African-Americans with Caucasians. ¶P=0.053 comparing men with women. **P=0.12 comparing African-Americans with Caucasians.”
First-two-assessments negative-group thrombosis rate is misstated
MinorThe 81 events over 5178 person-years give 1.56 events per 100 person-years, which rounds to 1.6 rather than the reported 1.5.
Reported 1.5 · recomputed 1.564311
“| No | 81 | 5178 | 1.5 | 1.00 (ref) | | 1.00 (ref) | |”
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Antiphospholipid patterns predict risk of thrombosis in systemic lupus erythematosus
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BackgroundInfluentialSelf-citationMishra, R. K., Kavadichanda, C. G., Baskaran, P., et al. (2026) · Lara D. Veeken · doi:10.1093/rheumatology/keag407
- Authors
- Petri, M. A., Avci, M., & Magder, L. S.
- Affiliations
- Johns Hopkins University (US)
- Istanbul University (TR)
- University of Maryland, Baltimore (US)
- Corresponding author
- Petri, Michelle A
- Venue
- Lupus Science & Medicine
- Publisher
- BMJ
- Published
- 2020-11
- Volume
- 7
- Issue
- 1
- Pages
- e000406
- ISSN
- 2053-8790 (ISSN-L)
- PMC
- PMC7607609
- OpenAlex
- W3096980036
- Cited by
- 6
- References
- 22
- Citations by year
- 2026: 1 · 2024: 1 · 2022: 2 · 2021: 1 · 2020: 1
- FWCI
- 0.64
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- Lupus Science & Medicine (publishedVersion, cc-by-nc)
- PubMed (publishedVersion)
- PubMed Central (submittedVersion, cc-by-nc)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01 AR069572)
- Topics
- Health Sciences › Medicine › Rheumatology › Systemic Lupus Erythematosus Research
- Health Sciences › Medicine › Hematology › Blood Coagulation and Thrombosis Mechanisms
- Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Vasculitis and related conditions
- Keywords
- lupus anticoagulant, systemic lupus erythematosus, thrombosis risk, antiphospholipid antibodies, retesting, screening frequency, prevalence, sex differences
- MeSH terms
- Adult, Female, Humans, Lupus Erythematosus, Systemic, Male, Middle Aged, Thrombosis, Lupus Coagulation Inhibitor, Antiphospholipid Syndrome
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-08.
Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-08.
Cited sources are checked by gpt-6-sol.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
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