Safety and efficacy of malaria vaccine candidate R21/Matrix-M in African children: a multicentre, double-blind, randomised, phase 3 trial.
Datoo MS, Dicko A, Tinto H, Ouédraogo JB, Hamaluba M, Olotu A, Beaumont E, Ramos Lopez F, Natama HM, Weston S, Chemba M, Compaore YD, Issiaka D, Salou D, Some AM, Omenda S, Lawrie A, Bejon P, Rao H, Chandramohan D, Roberts R, Bharati S, Stockdale L, Gairola S, Greenwood BM, Ewer KJ, Bradley J, Kulkarni PS, Shaligram U, Hill AVS, R21/Matrix-M Phase 3 Trial Group
- DOI
- 10.1016/S0140-6736(23)02511-4
- Record issued
- 2026-08-16
- Engine
- 7.39.0
- Exported
- 2026-09-20
Prepared by Alpha1. This document is confidential: it is intended for the recipient it was shared with and must not be redistributed. The live record at alpha1science.com/verify/19f09cac-2c9c-489d-98ba-772f19b1f39e is authoritative.
How this rating was calculated
- IntegrityIntegrity concern ×2−1★
- CitationsUnresolved reference−0.25★
- No data or code availability links were detected to verify.
This Kaimen Rigor review uses Kaimen Rigor reviewers trained on a curated corpus of high-fidelity and retracted papers, with expert supervision and curation. It can still make mistakes; verify each finding against the source before relying on it.
This is a well-conducted and transparently reported phase 3 randomized controlled trial of the R21/Matrix-M malaria vaccine. The paper demonstrates strong scientific premise, rigorous design, comprehensive reporting of biological variables, ethical approvals, key resources, statistical analysis, data availability, and transparency. Minor issues include a few copyediting inconsistencies and a single reference that could not be found in registries.
Both reviewers independently scored all eight dimensions and agreed on every status. The study type is interventional (phase 3 RCT). The statistics verification recomputed 8 reported tests consistently; the citation check flagged 1 reference not found in registries; the integrity check noted a minor discrepancy in Table 2 (N=3102 vs 3103) that is likely a rounding issue.
Numerical inconsistencies
1 finding · worst lowValues that contradict each other or are impossible for the stated sample: recomputed p-values and test statistics, GRIM/GRIMMER checks on summary numbers, percentages against their own counts, totals against their parts, and estimates against their own confidence intervals.
- Internal contradictions in the reported numbersAssessed
Recomputed 8 tests: 8 consistent, 0 inconsistent; 8 via agent-written checks.
- CONSISTENTreported p < .001 · recomputed p = <.001Reviewer 1Vaccine efficacy at seasonal sites (time to first episode) from reported HR and CI.
“12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites”
Taken as given: The reported efficacy is a hazard ratio (log scale).; The CI is a 95% confidence interval.; The p-value is two-sided.Method: Recomputed p-value from the reported efficacy and 95% CI using the pCI function for a ratio.How we recomputed it: pCI(0.75, 0.71, 0.79, 1) - CONSISTENTreported p < .001 · recomputed p = <.001Reviewer 1Vaccine efficacy at standard sites (time to first episode) from reported HR and CI.
“12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites and 68% (61–74; p<0·0001) at the standard sites”
Taken as given: The reported efficacy is a hazard ratio (log scale).; The CI is a 95% confidence interval.; The p-value is two-sided.Method: Recomputed p-value from the reported efficacy and 95% CI using the pCI function for a ratio.How we recomputed it: pCI(0.68, 0.61, 0.74, 1) - CONSISTENTreported p < .001 · recomputed p = <.001Reviewer 2Vaccine efficacy at seasonal sites for time to first episode: 75% (95% CI 71-79), p<0.0001. Recompute p from CI using pCI function.
“12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites”
Taken as given: The estimate is a hazard ratio (log scale).; The CI is a 95% confidence interval.; The p-value is two-sided.Method: Used pCI function with log=1 for hazard ratio.How we recomputed it: pCI(0.75, 0.71, 0.79, 1) - CONSISTENTreported p < .001 · recomputed p = <.001Reviewer 2Vaccine efficacy at standard sites for time to first episode: 68% (95% CI 61-74), p<0.0001. Recompute p from CI.
“12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites and 68% (61–74; p<0·0001) at the standard sites”
Taken as given: The estimate is a hazard ratio (log scale).; The CI is a 95% confidence interval.; The p-value is two-sided.Method: Used pCI function with log=1 for hazard ratio.How we recomputed it: pCI(0.68, 0.61, 0.74, 1) - CONSISTENTreported p < .001 · recomputed p = <.001Reviewer 2Vaccine efficacy at seasonal sites for multiple episodes: 75% (95% CI 71-78), p<0.0001. Recompute p from CI.
“Similarly, vaccine efficacy against multiple clinical malaria episodes was 75% (71–78; p<0·0001) at the seasonal sites”
Taken as given: The estimate is a hazard ratio (log scale).; The CI is a 95% confidence interval.; The p-value is two-sided.Method: Used pCI function with log=1 for hazard ratio.How we recomputed it: pCI(0.75, 0.71, 0.78, 1) - CONSISTENTreported p < .001 · recomputed p = <.001Reviewer 2Vaccine efficacy at standard sites for multiple episodes: 67% (95% CI 59-73), p<0.0001. Recompute p from CI.
“Similarly, vaccine efficacy against multiple clinical malaria episodes was 75% (71–78; p<0·0001) at the seasonal sites and 67% (59–73; p<0·0001) at standard sites.”
Taken as given: The estimate is a hazard ratio (log scale).; The CI is a 95% confidence interval.; The p-value is two-sided.Method: Used pCI function with log=1 for hazard ratio.How we recomputed it: pCI(0.67, 0.59, 0.73, 1) - CONSISTENTreported p < .001 · recomputed p = <.001Reviewer 2Vaccine efficacy at seasonal sites for 5-17 month age group: 79% (95% CI 73-84), p<0.001. Recompute p from CI.
“the younger age group had the highest 12-month vaccine efficacy on time to first clinical malaria episode at seasonal (79% [95% CI 73–84]; p<0·001)”
Taken as given: The estimate is a hazard ratio (log scale).; The CI is a 95% confidence interval.; The p-value is two-sided.Method: Used pCI function with log=1 for hazard ratio.How we recomputed it: pCI(0.79, 0.73, 0.84, 1) - CONSISTENTreported p < .001 · recomputed p = <.001Reviewer 2Vaccine efficacy at standard sites for 5-17 month age group: 75% (95% CI 65-83), p<0.001. Recompute p from CI.
“and standard (75% [65–83]; p<0·001) sites.”
Taken as given: The estimate is a hazard ratio (log scale).; The CI is a 95% confidence interval.; The p-value is two-sided.Method: Used pCI function with log=1 for hazard ratio.How we recomputed it: pCI(0.75, 0.65, 0.83, 1)
- lowinternal contradictionThe abstract states 5477 children consented to be screened, while the results section states 5477 children aged 5–36 months consented to be screened. This is consistent, but the number of randomized participants differs: abstract says 1705 control and 3434 R21/Matrix-M, results says 5139 randomized. The abstract says 1705+3434=5139, which matches. No contradiction.
“From April 26, 2021, to Jan 12, 2022, 5477 children consented to be screened, of whom 1705 were randomly assigned to control vaccine and 3434 to R21/Matrix-M; 4878 participants received the first dose of vaccine.”
AbstractFind in source - lowinternal contradictionIn Table 2, the number of participants with 0 episodes plus those with 1, 2, 3+ episodes should equal the total N. For the control group at all sites, 914+341+139+147 = 1541, which matches the N. For R21/Matrix-M, 2639+335+88+41 = 3103, but the table shows N=3102. This is a minor discrepancy of 1, possibly due to rounding or a missing data point.
“R21/Matrix-M | 3102 | 2639 (85·1) | 335 (10·8%) | 88 (2·8%) | 41 (1·3%)”
Table 2Find in source
Overstated conclusions
1 finding · worst lowConclusions that reach past what the paper's own results support — including a significance claim that no longer holds when the statistic is recomputed, and efficacy resting on an unvalidated surrogate endpoint.
- Conclusions only partially backed by the presented evidenceAssessed
6 major claims checked against the paper's own evidence: 1 only partially supported (evidence backs part of the claim; gaps or caveats remain); the rest adequately supported.
- partialReviewer 2R21/Matrix-M could contribute to reducing malaria transmission.The paper shows reduced asymptomatic parasitaemia in the vaccine group, suggesting a potential transmission reduction, but this is not a direct measure of transmission.Evidence: Cross-sectional blood film results at 12 and 18 months.
“This finding suggests that the R21/Matrix-M vaccine might not only substantially decrease the number of clinical malaria cases, but could also contribute to programmes to reduce malaria transmission when used with other interventions, particularly if deployed across a wider age range.”
Discussion ¶3Find in source - supportedReviewers 1, 2R21/Matrix-M vaccine efficacy is 75% at seasonal sites and 68% at standard sites against clinical malaria.The reported efficacy estimates are directly supported by the primary analysis results.Evidence: Primary analysis results in Table 2 and text.
“12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites and 68% (61–74; p<0·0001) at the standard sites for time to first clinical malaria episode.”
AbstractFind in source - supportedReviewer 1R21/Matrix-M is well tolerated.Safety data show no significant differences in serious adverse events and no treatment-related deaths.Evidence: Safety results section.
“R21/Matrix-M vaccine was well tolerated, with injection site pain (301 [18·6%] of 1615 participants) and fever (754 [46·7%] of 1615 participants) as the most frequent adverse events.”
AbstractFind in source - supportedReviewers 1, 2Vaccine-induced NANP-specific antibodies correlate with vaccine efficacy.The paper reports higher antibody titres in the younger age group, which also had higher efficacy, and a correlation is stated.Evidence: Immunogenicity results and correlation analysis.
“Vaccine-induced antibodies against the conserved central Asn-Ala-Asn-Pro (NANP) repeat sequence of circumsporozoite protein correlated with vaccine efficacy.”
AbstractFind in source - supportedReviewers 1, 2R21/Matrix-M offers high efficacy in the extended age range of 5-36 months.The trial enrolled children aged 5-36 months and demonstrated high efficacy in this group.Evidence: Primary efficacy results in the full cohort.
“In this phase 3 licensure trial of the R21/Matrix-M malaria vaccine, the primary analysis shows vaccine efficacy against clinical malaria of 75% (72–79) at seasonal sites and 67% (59–73) at standard sites across the entire cohort aged 5–36 months over 12 months.”
Discussion ¶1Find in source - supportedReviewer 2R21/Matrix-M is well tolerated with no treatment-related deaths.Safety data show no treatment-related deaths and no significant differences in serious adverse events.Evidence: Safety results section, Table 4.
“There were no treatment-related deaths.”
AbstractFind in source
Efficacy claim is anchored to an adequate endpoint and a meaningful effect.
- ADEQUATESurrogate endpointThe primary endpoint is clinical malaria (fever plus parasitemia >5000/µL), a clinical outcome, not a surrogate. The paper also reports a correlate of protection (NANP-specific antibody titers) but this is secondary and not the basis for the efficacy claim.
“The primary case definition of clinical malaria was the presence of an axillary temperature (≥37·5°C), or history of fever within the past 24 h, and P falciparum asexual parasite density of more than 5000 parasites per μL of blood using passive case detection.”
- ADEQUATEEffect sizeVaccine efficacy of 75% at seasonal sites and 68% at standard sites for time to first clinical malaria episode, with narrow confidence intervals and p<0.0001. This is a large effect on a clinical outcome, clearly clinically meaningful.
“12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites and 68% (61–74; p<0·0001) at the standard sites for time to first clinical malaria episode.”
Data authenticity concerns
None foundAn adversarial read for patterns associated with data that may not be genuine: results that look too clean, implausibly large effects, duplicated data or images, and methods that do not match the results reported.
Checked — nothing surfaced.
Reporting gaps
None foundRequired detail the manuscript never states — study design, biological variables, ethics approval and consent, key resources, statistical reporting, data and code availability, and overall transparency.
Checked — nothing surfaced.
The introduction cites prior work on RTS,S/AS01 and R21/Matrix-M, acknowledging both strengths (efficacy) and limitations (insufficient supply, waning efficacy). The rationale for the trial is clearly stated: to assess efficacy in an extended age range (5-36 months) and with different transmission settings. The paper also addresses limitations of prior research, such as the need for a low-cost, high-efficacy vaccine with scalable supply.
“In the phase 3 trial of RTS,S/AS01, a circumsporozoite protein-based vaccine, vaccine efficacy in children aged 5–17 months with a four-dose regimen was 56% over 1 year and 36% over 4 years.”
“In this multicentre, double-blind, randomised, phase 3 trial, we aimed to assess the safety and efficacy of R21/Matrix-M vaccine in the extended age range of 5–36 months of age at the first dose, rather than from 5–17 months.”
“However, the initial supply of this four-dose vaccine (18 million doses over 3 years) is insufficient for coverage of all children born in regions with moderate-to-high malaria transmission (over 25 million children annually).”
“In the phase 3 trial of RTS,S/AS01, a circumsporozoite protein-based vaccine, vaccine efficacy in children aged 5–17 months with a four-dose regimen was 56% over 1 year and 36% over 4 years.”
“In this multicentre, double-blind, randomised, phase 3 trial, we aimed to assess the safety and efficacy of R21/Matrix-M vaccine in the extended age range of 5–36 months of age at the first dose, rather than from 5–17 months.”
“However, the initial supply of this four-dose vaccine (18 million doses over 3 years) is insufficient for coverage of all children born in regions with moderate-to-high malaria transmission (over 25 million children annually).”
Randomization was done using an electronic interactive web response system with block randomization, stratified by site, age, and sex. Blinding was comprehensive: participants, families, investigators, laboratory teams, and local study team were masked. A power analysis is provided for both seasonal and standard sites. Inclusion/exclusion criteria are described, and the modified per-protocol population is defined. Outlier handling is addressed through the definition of analysis populations and missing data handling.
“Randomisation was done using an electronic interactive web response system (DiagnoSearch Life, Thane, India). Randomisation was stratified by trial site (seasonal or standard), and potential confounders, including age (5–12 months, 13–24 months, or 25–36 months) and sex (male or female), using block randomisation with variable block sizes.”
“The trial was double-blinded: participants, their families, all investigators, the laboratory teams, and the local study team were all masked to treatment.”
“At the seasonal sites, the expected incidence rate was 0·58 cases per child per year among the 800 control participants which, with 12 months’ follow-up, would give more than 95% power to exclude a lower limit of efficacy of 30% if the vaccine efficacy was at least 50%.”
“Randomisation was done using an electronic interactive web response system (DiagnoSearch Life, Thane, India). Randomisation was stratified by trial site (seasonal or standard), and potential confounders, including age (5–12 months, 13–24 months, or 25–36 months) and sex (male or female), using block randomisation with variable block sizes.”
“The trial was double-blinded: participants, their families, all investigators, the laboratory teams, and the local study team were all masked to treatment.”
“At the seasonal sites, the expected incidence rate was 0·58 cases per child per year among the 800 control participants which, with 12 months’ follow-up, would give more than 95% power to exclude a lower limit of efficacy of 30% if the vaccine efficacy was at least 50%.”
The paper reports sex distribution (male/female), age (mean and SD), weight, and weight-for-age Z-scores in Table 1. Health status is implied through inclusion/exclusion criteria. Demographics are reported for the modified per-protocol population. Since both sexes are enrolled, sex_justified is not applicable.
“Male | 1607/3103 (51·8%) | 805/1541 (52·2%) | 2412/4644 (51·9%)”
“Age, months | 19·1 (9·0) | 18·9 (9·0) | 19 (9·0)”
“Male | 1607/3103 (51·8%) | 805/1541 (52·2%) | 2412/4644 (51·9%)”
“Age, months | 19·1 (9·0) | 18·9 (9·0) | 19 (9·0)”
The trial was approved by local ethics committees and regulatory authorities, as well as ethics committees at the University of Oxford and LSHTM. Informed consent was obtained from parents/guardians, with written or thumb-printed consent. Regulatory compliance is implied through approval by regulatory authorities.
“The trial was approved by all the local ethics committees and regulatory authorities, as well as the ethics committees at the University of Oxford (Oxford, UK) and The London School of Hygiene & Tropical Medicine (London, UK), with supportive coordination by the African Vaccine Regulatory Forum.”
“Before screening, parents or guardians of participants provided written or thumb-printed consent, which was verbally re-checked at every study visit.”
“The trial was approved by all the local ethics committees and regulatory authorities, as well as the ethics committees at the University of Oxford (Oxford, UK) and The London School of Hygiene & Tropical Medicine (London, UK), with supportive coordination by the African Vaccine Regulatory Forum.”
“Before screening, parents or guardians of participants provided written or thumb-printed consent, which was verbally re-checked at every study visit.”
The R21 vaccine is identified as from Serum Institute of India, Matrix-M from Novavax AB, and the control vaccine Abhayrab from Indian Immunologicals. Doses are specified. Statistical software (Stata version 17) is identified. No antibodies, cell lines, or other bench reagents are used, so those criteria are not applicable.
“Participants received R21 (Serum Institute of India) as a two-vial formulation: R21 was mixed immediately before administration with the saponin-based vaccine adjuvant Matrix-M (Novavax AB, Uppsala, Sweden). A dose of 5 μg R21 with 50 μg Matrix-M was used in the trial. A licensed rabies vaccine (Abhayrab; Indian Immunologicals, Hyderabad, India) was the control vaccine.”
“All statistical analyses were performed using Stata version 17.”
“Participants received R21 (Serum Institute of India) as a two-vial formulation: R21 was mixed immediately before administration with the saponin-based vaccine adjuvant Matrix-M (Novavax AB, Uppsala, Sweden).”
“A licensed rabies vaccine (Abhayrab; Indian Immunologicals, Hyderabad, India) was the control vaccine.”
“All statistical analyses were performed using Stata version 17.”
The primary analysis uses Cox regression, and secondary analyses use Cox regression with robust standard errors and log-binomial models. Effect sizes are reported as vaccine efficacy with 95% CIs. Exact p-values are reported (e.g., p<0·0001). Data presentation includes Kaplan-Meier curves and tables with per-group n. Mathematical plausibility checks were not performed due to large N and continuous outcomes, but no obvious inconsistencies were noted.
“The primary analysis was time to first episode of clinical malaria and was analysed by Cox regression stratified by study site (seasonal or standard).”
“12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites and 68% (61–74; p<0·0001) at the standard sites for time to first clinical malaria episode.”
“The primary analysis was time to first episode of clinical malaria and was analysed by Cox regression stratified by study site (seasonal or standard).”
“12-month vaccine efficacy was 75% (95% CI 71–79; p<0·0001) at the seasonal sites and 68% (61–74; p<0·0001) at the standard sites for time to first clinical malaria episode.”
“All statistical analyses were performed using Stata version 17.”
The data availability statement provides a concrete access route: requests directed to the corresponding author, reviewed by sponsor and investigators, and shared through a secure online platform after a data access agreement. This is adequate for patient-level data. Repository deposit and accession numbers are not applicable for identifiable patient data. Code sharing is not applicable as no bespoke code is mentioned.
“Anonymised participant data will be made available when the trial is complete, upon requests directed to the corresponding author. Proposals will be reviewed and approved by the sponsor, investigators, and collaborators based on scientific merit. After approval of a proposal, data can be shared through a secure online platform after signing a data access agreement.”
“Anonymised participant data will be made available when the trial is complete, upon requests directed to the corresponding author. Proposals will be reviewed and approved by the sponsor, investigators, and collaborators based on scientific merit. After approval of a proposal, data can be shared through a secure online platform after signing a data access agreement.”
The trial is registered on ClinicalTrials.gov (NCT04704830). Methods are detailed enough for replication. Limitations are discussed, including lack of power for severe malaria and individual sites. Conclusions are proportional to evidence. Funding sources and conflicts of interest are declared. Reporting guideline adherence is not explicitly stated, but the paper follows standard reporting.
“This study is registered on ClinicalTrials.gov, NCT04704830 (https://clinicaltrials.gov/ct2/show/NCT04704830) .”
“This study had some limitations. The trial was not powered to assess vaccine efficacy against clinical malaria at individual sites nor efficacy against mortality or severe malaria across all sites.”
“This study is registered on ClinicalTrials.gov, NCT04704830 (https://clinicaltrials.gov/ct2/show/NCT04704830) .”
“This study had some limitations. The trial was not powered to assess vaccine efficacy against clinical malaria at individual sites nor efficacy against mortality or severe malaria across all sites.”
“The Serum Institute of India, the Wellcome Trust, the UK National Institute for Health Research Oxford Biomedical Research Centre, and Open Philanthropy.”
Registered (3 IDs: ClinicalTrials.gov). No reporting guideline cited.
Broken references and links
1 finding · worst lowReferences checked against Crossref, OpenAlex and Retraction Watch for retractions and resolvability, plus declared data and code links probed for whether they resolve to content matching the paper.
- References not resolvable to a published paperRecomputed
Checked 11 references by DOI: 5 verified — 1 DOI unresolved, 5 no DOI (shown, not verified).
- UNRESOLVED10.1101/19009282v1.fullPhase I assessments of first-in-human administration of a novel malaria anti-sporozoite vaccine candidate, R21 in matrix-M adjuvant, in UK and Burkinabe volunteersCited DOI does not resolve to any Crossref record.
- NO DOIWorld malaria report 2022No DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIFull evidence report on the RTS.S.AS01 malaria vaccineNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIFirst malaria vaccine supply allocations May 2023No DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIFramework for the allocation of limited malaria vaccine supplyNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIHigh level efficacy in humans of a next-generation Plasmodium falciparum anti-sporozoite vaccine: R21 in Matrix-M (TM) adjuvantNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
Copyediting
9 minorWording, consistency and formatting errors that need correcting before submission.
No major wording or formatting errors. 9 minor suggestions below.
9 copyedit issues flagged: mostly consistency, typo.
- MINORtypoAbstract, Findings“recevied”→ receivedTypo in funding statement.
- MINORconsistencyTable 2, East African sites“0·56 (0·40– 0·68)”→ 0·56 (0·40–0·68)Inconsistent spacing in CI.
- MINORconsistencyTable 2, Kilifi site“0.37 (69/185·0)”→ 0·37 (69/185·0)Inconsistent decimal separator.
- MINORconsistencyTable 2, East African sites“78’3%”→ 78·3%Incorrect apostrophe used as decimal point.
- MINORtypoAcknowledgments“recevied”→ receivedTypographical error in the word 'received'.
- MINORconsistencyTable 2“0.37 (69/185·0)”→ 0·37 (69/185·0)Inconsistent use of decimal point vs middle dot in the Kilifi control row.
- MINORconsistencyTable 2“0.0003”→ 0·0003Inconsistent use of decimal point vs middle dot in p-value.
- MINORconsistencyTable 2“78’3%”→ 78·3%Inconsistent use of apostrophe instead of middle dot in percentage.
- MINORconsistencyTable 2“89.7%”→ 89·7%Inconsistent use of decimal point vs middle dot in percentage.
The published work is robust and well-reported. An informed reader should weigh the minor Table 2 discrepancy and the unresolved reference as low-severity issues that do not undermine the main conclusions. No erratum is warranted for the copyediting issues, but the authors may consider a correction for the Table 2 N discrepancy if it is confirmed.
- 1.HIGHreportingVerify and correct the reference 'Phase I assessments of first-in-human administration of a novel malaria anti-sporozoite vaccine candidate, R21 in matrix-M adjuvant, in UK and Burkinabe volunteers' (DOI 10.1101/19009282v1.full) that could not be found in any registry; if it is a preprint, provide the correct DOI or a published version.An unresolved reference may be a fabrication signal and must be verified or corrected.
- 2.MEDIUMreportingAdd an explicit statement in the Methods or Acknowledgments that the trial adheres to the CONSORT reporting guideline.Both reviewers noted that reporting guideline adherence is not explicitly stated, which is a minor transparency gap.
- 3.MEDIUMdata codeClarify the data sharing timeline in the Data sharing statement by specifying a concrete date or timeframe (e.g., 'within 12 months of trial completion') instead of 'when the trial is complete'.The current statement is vague about when data will become available, which could hinder reproducibility.
- 4.MEDIUMdata codeConsider sharing the statistical analysis code (e.g., Stata do-files) alongside the data availability statement.Sharing code would enhance transparency and reproducibility, even though no bespoke code is currently mentioned.
- 5.MEDIUMreportingAdd a link to the statistical analysis plan or full protocol in the Data sharing statement or Methods.Providing the SAP would allow readers to verify that the analysis was pre-specified.
- 6.LOWcopyeditFix the typo 'recevied' to 'received' in the Abstract (Findings) and Acknowledgments.Typographical errors detract from professionalism.
- 7.LOWcopyeditStandardize decimal separators in Table 2 to use the middle dot (·) consistently (e.g., change '0.37' to '0·37', '0.0003' to '0·0003', '89.7%' to '89·7%').Inconsistent decimal separators are a copyediting issue that could confuse readers.
- 8.LOWcopyeditFix spacing in confidence intervals in Table 2 (e.g., change '0·56 (0·40– 0·68)' to '0·56 (0·40–0·68)').Inconsistent spacing in CIs is a minor formatting issue.
- 9.LOWcopyeditReplace the apostrophe used as a decimal point in Table 2 (e.g., '78’3%' should be '78·3%').Incorrect use of apostrophe as decimal point is a typographical error.
- 10.LOWrigorInvestigate and clarify the minor discrepancy in Table 2 where the R21/Matrix-M group N is 3102 but the sum of episode counts is 3103.The integrity check flagged this internal inconsistency; it is likely a rounding or data entry error that should be corrected or explained.
The star rating is the report’s one-glance summary. Every paper starts at 5★ and loses stars for the concrete problems the review finds — so a rating is never a vague average, it’s a running total you can read line by line under “How this rating was calculated.”
- Reporting — 8 dimensionseach dimension that fully fails−½★
- each dimension partially met−¼★
- Statistics · Integrity · Claimseach serious problem−1★
- each medium problem−½★
- Citationseach retracted or unverifiable reference−¼★
- Copyeditonly when the manuscript needs a full edit−½★
The rating never drops below 1★, and a demonstrable critical failure (an impossible statistic, a proven ethics violation) caps it at 1★ on its own — so the stars can never look healthy when the verdict is CRITICAL.
The rating draws on a panel of agents. Three independent Kaimen Rigor reviewers grade the eight dimensions below across several independent passes (the shown verdict is their majority vote — steadier than any single run), isolate the paper’s major claims and check its own evidence backs them, and flag integrity concerns. Alongside them, a citation agent resolves every reference against Crossref, OpenAlex, and Retraction Watch; a statistics agent recomputes reported tests; and rule-based checks verify that declared data/code links actually resolve. Full text is required — an abstract-only submission is not analyzed.
Graded against NIH, MDAR, ARRIVE 2.0, CONSORT, EQUATOR, and RRID guidelines. A dimension that doesn’t apply to the study type is skipped, never penalized.
This Kaimen Rigor review is model-assisted and is not a substitute for formal expert review. It complements human evaluation by surfacing potential methodological concerns — verify each finding against the source.