Kaimen Rigor reviewed

Rigor-Reviewed Manuscript

Colonoscopy and fecal immunochemical testing versus usual care in diagnostic colorectal cancer screening: the SCREESCO randomized controlled trial.

Name: Kaimen Rigor review — Colonoscopy and fecal immunochemical testing versus usual care in diagnostic colorectal cancer screening: the SCREESCO randomized controlled trial.
Item: Colonoscopy and fecal immunochemical testing versus usual care in diagnostic colorectal cancer screening: the SCREESCO randomized controlled trial.
Rating: 100
Author: Alpha1

Westerberg M, Ludvigsson JF, Metcalfe C, Strömberg U, Blom J, Engstrand L, Hellström M, Löwbeer C, Steele R, Holmberg L, Forsberg A

Paper source

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Kaimen Rigor review — 2.5★ (Weak), 0 critical, 2 high issues for “Colonoscopy and fecal immunochemical testing versus usual care in diagnostic colorectal cancer screening: the SCREESCO randomized controlled trial.”

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Alpha1 Editorial

This rigor review was examined and confirmed by Alpha1 Editorial · August 15, 2026

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Colonoscopy and fecal immunochemical testing versus usual care in diagnostic colorectal cancer screening: the SCREESCO randomized controlled trial.

Westerberg M, Ludvigsson JF, Metcalfe C, Strömberg U, Blom J, Engstrand L, Hellström M, Löwbeer C, Steele R, Holmberg L, Forsberg A

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DOI

10.1038/s41591-026-04225-9

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Kaimen Rigor reviewed

Rigor-Reviewed Manuscript

Colonoscopy and fecal immunochemical testing versus usual care in diagnostic colorectal cancer screening: the SCREESCO randomized controlled trial.

Westerberg M, Ludvigsson JF, Metcalfe C, Strömberg U, Blom J, Engstrand L, Hellström M, Löwbeer C, Steele R, Holmberg L, Forsberg A

Paper source

Colonoscopy and fecal immunochemical testing versus usual care in diagnostic colorectal cancer screening: the SCREESCO randomized controlled trial.

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Alpha1 Editorial

This rigor review was examined and confirmed by Alpha1 Editorial · August 15, 2026

Kaimen Rigor review

Kaimen Rigor reviewed

2.5 / 5

Weak — serious problems found

Interventional Study

Critical

High-priority

How this rating was calculated▸

Started at 5★ — deductions

IntegrityIntegrity concern ×3−1.5★
ClaimsEfficacy rests on an unvalidated surrogate endpoint−0.5★
ClaimsTreatment effect not shown to be clinically meaningful−0.5★

Model-reported confidence: highReviewer agreement: highEngine: 7.39.0Source: full text

Biggest issues

01Efficacy rests on an unvalidated surrogate endpoint
highOverreachreviewer-assessedFull detail
The primary efficacy claim is based on an increase in detection of early-stage (I–II) colorectal cancer, which is a surrogate for the ultimate clinical outcome of reduced CRC mortality. The paper does not demonstrate target engagement at the tested dose (e.g., PK/PD linking the screening intervention to the surrogate) nor cite validated evidence that an increase in stage I–II detection alone translates into reduced CRC mortality. The authors acknowledge that the trial duration is too short to detect a net benefit in CRC incidence or mortality, and that the excess early-stage cancers may represent overdiagnosis.
“The duration of the trial is likely too short to detect a net benefit of the prevention in terms of a lower CRC incidence in the intervention arms compared to controls and/or to determine if a part of the early-stage CRC excess risk in the intervention arms…”
Find in source
02Treatment effect not shown to be clinically meaningful
highOverreachreviewer-assessedFull detail
The primary reported effect is an increase in stage I–II CRC detection (IRR 1.38 for colonoscopy, 1.19 for FIT), but the absolute rates are small (58.7 vs 42.5 per 100,000 person-years for colonoscopy) and the paper does not anchor this to a minimal clinically important difference or demonstrate that this translates into a meaningful clinical benefit. The authors note that the trial is underpowered for mortality and that the increase may represent overdiagnosis.
“The duration of the trial is likely too short to detect a net benefit of the prevention in terms of a lower CRC incidence in the intervention arms compared to controls and/or to determine if a part of the early-stage CRC excess risk in the intervention arms…”
Find in source

Findings by category

101ArithmeticNumerical inconsistencies 302OverreachOverstated conclusions 103AuthenticityData authenticity concerns 04DisclosureNone found 05AvailabilityNone found 06Copyedit6 minor suggestions

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 randomized controlled trial. The methods are rigorous, ethical approvals are documented, and data/code availability is exemplary. The only notable issues are minor reporting gaps (no explicit CONSORT statement) and a few copyedit-level inconsistencies in numbers.

Both reviewers classified the study as interventional (RCT), and I adopt that classification. The evaluation covered the full text, with verification components for citations, statistics, reproducibility, and preregistration. Non-applicable sub-criteria (e.g., animal housing, cell lines) were excluded. The reviewers diverged only on whether the reporting guideline was 'reported but inadequate' or 'not reported'; I synthesized as 'reported but inadequate' since the paper follows a structured format but lacks an explicit CONSORT statement.

Numerical inconsistencies

1 finding · worst low

Values 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 2 tests: 2 consistent, 0 inconsistent; 2 via agent-written checks.

Overstated conclusions

3 findings · worst high

Conclusions 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.

Efficacy rests on an unvalidated surrogate endpointAssessed
Treatment effect not shown to be clinically meaningfulAssessed
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.

Premise concern: surrogate not validated for clinical benefit; effect size not shown to be clinically meaningful.

Data authenticity concerns

1 finding · worst low

An 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.

Other integrity concernAssessed

3 integrity concerns flagged (0 high).

Reporting gaps

None found

Required 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.

Eight Dimensions8 pass

The introduction cites guidelines and prior trials (COLONPREV, NordICC) and notes the limited evidence from RCTs on primary colonoscopy and FIT versus usual care. The rationale for the study is logically derived from these gaps, and the study aims to quantify benefits and harms. Limitations of prior work are implicitly addressed by the trial's design (e.g., including a control arm).

Sub-criteria

prior work citedADEQUATE

premise rationaleADEQUATE

limitations addressedADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

The paper establishes a clear scientific premise by citing prior research on CRC screening and identifying gaps in evidence, particularly the lack of RCTs comparing FIT to usual care.

Evidence

paraphrase[Main, paragraph 1]

“There are several trials of colonoscopy screening, but few have examined FIT compared to usual care.”

“The aim of the present study was to assess if the randomization has resulted in the three arms being similar in terms of baseline demographic variables and medical history and to assess if the screening approaches resulted in a higher rate of diagnosis of CRC during the diagnostic phase, especially stage I–II CRC, compared to usual care.”

Main, paragraph 2Find in source

paraphrase[Discussion, paragraph 1]

“Paraphrase: The paper notes that other ongoing RCTs (COLONPREV, CONFIRM) lack a control arm, whereas SCREESCO includes a usual care control.”

PASSReviewer 2· 90% conf

The paper establishes a clear scientific premise by citing prior research on CRC screening and identifying the gap in evidence for FIT versus usual care.

Evidence

“The American College of Gastroenterology and the European Society of Gastrointestinal Endoscopy recommend CRC screening in individuals aged 50–75 years by colonoscopy or FIT”

Main, paragraph 1Find in source

“There are several trials of colonoscopy screening, but few have examined FIT compared to usual care”

Main, paragraph 2Find in source

paraphrase[Discussion, paragraph 1]

“The only ongoing RCTs other than the SCREESCO trial, involving both primary colonoscopy and FIT, are the Spanish trial COLONPREV and the American trial Colonoscopy vs. Fecal Immunochemical Test in Reducing Mortality from Colorectal Cancer (CONFIRM), neither of which has a control arm.”

Randomization used a randomized block method with stratification by year, region, and sex. The unit of randomization is the individual. Blinding was not possible due to the nature of the intervention, which is stated. Power calculations were performed for the primary endpoint (CRC mortality) and revised due to lower participation. Inclusion/exclusion criteria are pre-specified. Outlier handling is addressed through intention-to-screen analysis and censoring. Controls are the usual care arm. Independent replication is not applicable for a single pivotal trial.

Sub-criteria

controlsADEQUATE

power analysisADEQUATE

blinding levelsADEQUATE

outlier handlingADEQUATE

randomization unitADEQUATE

inclusion exclusionADEQUATE

randomization methodADEQUATE

replicate distinctionN/A

independent replicationN/A

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 95% conf

The trial design is rigorous with clear randomization, pre-specified eligibility criteria, and a priori power calculations; blinding was not possible but is acknowledged.

Evidence

“a randomized block method was used to assign 201,000 individuals born 1954–1956 without prior CRC diagnosis to once-only primary colonoscopy, two rounds of FIT 2 years apart (FIT×2) or a usual care control arm”

MethodsFind in source

“Masking was not possible due to the nature of the trial.”

MethodsFind in source

“A priori, the study was powered to detect a 17.5% decrease in CRC mortality at 15 years in individuals invited to colonoscopy compared to the control arm and a 15% decrease in individuals invited to FIT compared to the control arm”

MethodsFind in source

PASSReviewer 2· 95% conf

The trial design is rigorous with clear randomization, pre-specified eligibility, and power calculations, though blinding was not possible.

Evidence

MethodsFind in source

“Masking was not possible due to the nature of the trial.”

MethodsFind in source

Sex is reported for all arms with balanced proportions. Age is fixed at 60 years. Demographics include educational level, country of birth, and comorbidity indices. Health status is captured via Charlson Comorbidity Index and prior events. Species/strain and housing conditions are not applicable for a human trial.

Sub-criteria

demographicsADEQUATE

sex reportedADEQUATE

sex justifiedN/A

age weight healthADEQUATE

housing conditionsN/A

species strain sourceN/A

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

Biological variables are well reported for a human trial: sex, age, and demographics are detailed; species/strain and housing are not applicable.

Evidence

“Men | 15,550 | (50.0) | 93,309 | (50.0) | 30,128 | (50.0) | 60,261 | (50.0)”

Table 1Find in source

“assigned 278,280 individuals aged 60 years”

AbstractFind in source

paraphrase[Table 1]

“Educational level | Low | 5,704 | (18.3) | 34,378 | (18.4) | 11,569 | (19.2) | 23,134 | (19.2)”

PASSReviewer 2· 90% conf

Biological variables are well reported for a human trial, including sex, age, and demographics.

Evidence

“Men | 15,550 | (50.0) | 93,309 | (50.0) | 30,128 | (50.0) | 60,261 | (50.0)”

Table 1Find in source

“assigned 278,280 individuals aged 60 years”

AbstractFind in source

paraphrase[Table 1]

“Educational level | Low | 5,704 | (18.3) | 34,378 | (18.4) | 11,569 | (19.2) | 23,134 | (19.2)”

The Stockholm Ethics Committee approved the study (2012/2058-31/3) and the review of medical charts (2015/1958-2). The Swedish Ethical Review Authority waived the need for informed consent for accessing pseudonymized register-based data (2022/01946-02 and 2022/06863-2). Written informed consent was obtained from invited individuals. Regulatory compliance is implied by adherence to Swedish ethical review processes.

Sub-criteria

iacuc statementN/A

informed consentADEQUATE

irb ethics statementADEQUATE

regulatory complianceADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 95% conf

Ethical approvals are clearly documented with named committees and protocol numbers, and informed consent is described.

Evidence

“The Stockholm Ethics Committee approved the study (2012/2058-31/3) and the review of medical charts (2015/1958-2).”

MethodsFind in source

“All individuals invited for screening signed a written informed consent for the procedure and for biobanking of samples.”

MethodsFind in source

“The Swedish Ethical Review Authority waived the need for informed consent for accessing pseudonymized register-based data (2022/01946-02 and 2022/06863-2).”

MethodsFind in source

PASSReviewer 2· 95% conf

Ethical approvals and consent are clearly documented.

Evidence

“The Stockholm Ethics Committee approved the study (2012/2058-31/3)”

MethodsFind in source

“All individuals invited for screening signed a written informed consent for the procedure and for biobanking of samples.”

MethodsFind in source

“The Swedish Ethical Review Authority waived the need for informed consent for accessing pseudonymized register-based data (2022/01946-02 and 2022/06863-2).”

MethodsFind in source

The FIT test uses a single OC-Sensor DIANA automated analyzer (Eiken Chemical). Colonoscopy is described as a procedure. Software used for analysis is R version 4.0.2 and Stata 13.1. Custom code is available on GitHub. Antibodies, cell lines, mycoplasma, and organisms are not applicable.

Sub-criteria

mycoplasma testingN/A

reagents identifiedADEQUATE

organisms identifiedN/A

antibodies identifiedN/A

cell line authenticationN/A

software tools identifiedADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

The investigational product (FIT kit and colonoscopy) is identified with manufacturer and analyzer; software is identified with version and code repository.

Evidence

“One central laboratory performed all FIT analyses using a single OC-Sensor DIANA automated analyzer (Eiken Chemical).”

MethodsFind in source

“Stata version 13.1 and R version 4.0.2 were used for power calculations. Analyses were performed using R version 4.0.2.”

Statistical analysisFind in source

“The code was written in R version 4.0.2 using RStudio and is available at https://github.com/MarcusWesterberg/CRCs-and-AEs-during-diagnostic-phase-of-SCREESCO”

Data availabilityFind in source

PASSReviewer 2· 90% conf

Key resources are adequately identified, including the FIT analyzer and statistical software.

Evidence

“One central laboratory performed all FIT analyses using a single OC-Sensor DIANA automated analyzer (Eiken Chemical).”

MethodsFind in source

“Stata version 13.1 and R version 4.0.2 were used for power calculations. Analyses were performed using R version 4.0.2.”

Statistical analysisFind in source

Poisson regression models were used to compute incidence rate ratios with 95% CIs. The paper reports effect sizes with CIs, which is the primary reporting style. Exact p-values are not reported, but the analysis is estimation-based, so this is not a deficiency. Assumptions of equidispersion were checked. Data presentation includes per-group Ns and rates with CIs. Mathematical plausibility checks were not performed due to large N and continuous outcomes.

Sub-criteria

tests namedADEQUATE

exact p valuesN/A

effect sizes ciADEQUATE

data presentationADEQUATE

software identifiedADEQUATE

assumptions verifiedADEQUATE

mathematical plausibilityN/A

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

Statistical methods are appropriate and well-described; effect sizes are reported with confidence intervals, and software is identified.

Evidence

“We compare each intervention arm with the corresponding control arm concerning each of the outcomes using incidence rates and IRRs using Poisson regression models with 95% CIs.”

Statistical analysisFind in source

“incidence rate ratio (IRR): 1.08, 95% confidence interval (CI): 0.91–1.28”

AbstractFind in source

“We assessed potential violations of equidispersion for each regression model and computed alternative CIs by use of robust standard errors.”

Statistical analysisFind in source

PASSReviewer 2· 90% conf

Statistical methods are appropriate and well reported, with effect sizes and confidence intervals.

Evidence

“We compare each intervention arm with the corresponding control arm concerning each of the outcomes using incidence rates and IRRs using Poisson regression models with 95% CIs.”

Statistical analysisFind in source

“We assessed potential violations of equidispersion for each regression model and computed alternative CIs by use of robust standard errors.”

Statistical analysisFind in source

“incidence rate ratio (IRR): 1.08, 95% confidence interval (CI): 0.91–1.28”

AbstractFind in source

The data availability statement explains that individual-level data cannot be shared publicly due to privacy and legislation, but provides a concrete route for access via the SCREESCO Steering Committee with conditions and timeframe. Code is available on GitHub. Repository deposit and accession numbers are not applicable for patient-level data.

Sub-criteria

code sharingADEQUATE

accession numbersN/A

repository depositN/A

data availability statementADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 95% conf

Data availability is clearly described with a managed-access mechanism, and code is shared in a public repository.

Evidence

“Selected deidentified individual participant data that underlie the results reported in this article (including in the supplementary materials) can, however, be made available to researchers after request to the SCREESCO Steering Committee.”

Data availabilityFind in source

“The code was written in R version 4.0.2 using RStudio and is available at https://github.com/MarcusWesterberg/CRCs-and-AEs-during-diagnostic-phase-of-SCREESCO”

Data availabilityFind in source

PASSReviewer 2· 95% conf

Data availability is well described with a managed access process, and code is shared in a public repository.

Evidence

Data availabilityFind in source

“The code was written in R version 4.0.2 using RStudio and is available at https://github.com/MarcusWesterberg/CRCs-and-AEs-during-diagnostic-phase-of-SCREESCO”

Data availabilityFind in source

The trial is registered (NCT02078804). Methods are detailed enough for replication. Limitations are explicitly discussed, including participation rates and potential misclassification. Conclusions are proportional, noting the diagnostic phase and future mortality outcomes. Funding and competing interests are declared. A reporting guideline is not explicitly mentioned, but the paper follows standard reporting.

Sub-criteria

funding coiADEQUATE

trial registrationADEQUATE

reporting guidelineINADEQUATE

methods completenessADEQUATE

all outcomes reportedADEQUATE

limitations discussedADEQUATE

conclusions proportionalADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

The manuscript is transparent with trial registration, detailed methods, discussion of limitations, and proportional conclusions.

Evidence

“ClinicalTrials.gov: NCT02078804”

AbstractFind in source

“This study also has some limitations.”

Discussion ¶5Find in source

“Financial support was provided by the Swedish regions (A.F.), Regional Cancer Center Mellansverige (A.F.), the Swedish Cancer Society (A.F.; 2018/595 and 2021/1628), the Aleris Research and Development Fund (A.F.) and Eiken Chemical (A.F.).”

AcknowledgementsFind in source

PASSReviewer 2· 90% conf

Reporting is transparent with trial registration, protocol amendments, and limitations discussed.

Evidence

“ClinicalTrials.gov: NCT02078804”

AbstractFind in source

“This study also has some limitations.”

Discussion ¶5Find in source

AcknowledgementsFind in source

Registered (1 ID: ClinicalTrials.gov). No reporting guideline cited.

Broken references and links

None found

References 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.

Checked — nothing surfaced.

Checked 40 references by DOI: 1 verified — 39 no DOI (shown, not verified).

5 data/code links checked; 5 live.

Copyediting

6 minor

Wording, consistency and formatting errors that need correcting before submission.

No major wording or formatting errors. 6 minor suggestions below.

6 copyedit issues flagged: mostly consistency, typo, clarity.

Kaimen Rigor Action ItemsFinal pass before journal submission

The published work is robust and methodologically sound. An informed reader should weigh the minor reporting gaps (no explicit CONSORT statement, minor number inconsistencies) and the fact that the primary mortality endpoint is not yet reported. No erratum is warranted for the copyedit issues, but the authors should consider a correction for the typo in Table 1 (17,2738) and clarify the randomized vs. analyzed numbers.

1.
HIGHcopyedit
Correct the typo in Table 1: change '17,2738' to '172,738' in the 'Any prior cardiovascular or gastrointestinal event' row.
This is a clear numerical typo that could mislead readers and should be corrected via an erratum.
2.
HIGHreporting
Add an explicit statement of adherence to CONSORT (or another reporting guideline) in the Methods or a Reporting Summary.
Both reviewers noted the absence of an explicit reporting guideline statement, which is a standard expectation for RCTs and would enhance transparency.
3.
MEDIUMreporting
Clarify the discrepancy between the number randomized (31,140 in Methods) and the number analyzed (31,113) in the primary colonoscopy arm, and similarly for the FIT arm (60,300 vs 60,267).
The integrity check flagged these internal contradictions; explaining the exclusions will prevent reader confusion.
4.
MEDIUMreporting
Clarify the total number randomized (278,280) versus the number analyzed (278,051) in the abstract or methods.
The copyedit noted this inconsistency; a brief explanation of exclusions would improve clarity.
5.
MEDIUMstatistics
Clarify in the Methods whether robust standard errors were used in the final analysis or only as a sensitivity check.
The copyedit flagged this ambiguity; specifying the primary analysis approach is important for reproducibility.
6.
MEDIUMreporting
Consider reporting exact p-values for key comparisons in addition to confidence intervals, or note that they are available on request.
Both reviewers suggested this to facilitate meta-analyses and provide more complete statistical reporting.
7.
MEDIUMdata code
Provide a DOI or versioned release for the GitHub code repository to ensure permanent access.
Reviewer 2 suggested this to improve long-term reproducibility.
8.
LOWreporting
Add a note on the generalizability of findings to other age groups, as the study only included 60-year-olds.
Reviewer 2 noted this limitation; a brief statement would help readers interpret the applicability.
9.
LOWreporting
Consider discussing the higher rate of venous thromboembolism in the FIT arm (IRR 1.39) in the abstract or discussion.
The integrity check noted this finding is not discussed in the abstract; highlighting it would improve balance.
10.
LOWcopyedit
Rephrase the abstract sentence 'fecal immunochemical testing (FIT) compared with usual care with no screening' to 'compared with usual care (no screening)' for clarity.
Minor clarity improvement suggested by the copyedit pass.

Full text (58,708 chars)Analyzed: Aug 15, 2026

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Read alongside

Colonoscopy and fecal immunochemical testing versus usual care in diagnostic colorectal cancer screening: the SCREESCO randomized controlled trial.

Westerberg M, Ludvigsson JF, Metcalfe C, Strömberg U, Blom J, Engstrand L, Hellström M, Löwbeer C, Steele R, Holmberg L, Forsberg A

Read full text (PMC)

DOI

10.1038/s41591-026-04225-9

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Record fingerprint

abd1267aa7a5b966bf5acfa0aeaef7ba957f7a68c6813aa27231fd8d683bd416

Verify via API

Issued Aug 15, 2026Engine 7.39.0

Alpha1 assesses methodological rigor, not the importance of the findings. See how we calibrate →

Kaimen Rigor review

Kaimen Rigor reviewed

2.5 / 5

Weak — serious problems found

Interventional Study

Critical

High-priority

How this rating was calculated▸

Started at 5★ — deductions

IntegrityIntegrity concern ×3−1.5★
ClaimsEfficacy rests on an unvalidated surrogate endpoint−0.5★
ClaimsTreatment effect not shown to be clinically meaningful−0.5★

Model-reported confidence: highReviewer agreement: highEngine: 7.39.0Source: full text

Biggest issues

01Efficacy rests on an unvalidated surrogate endpoint
highOverreachreviewer-assessedFull detail
The primary efficacy claim is based on an increase in detection of early-stage (I–II) colorectal cancer, which is a surrogate for the ultimate clinical outcome of reduced CRC mortality. The paper does not demonstrate target engagement at the tested dose (e.g., PK/PD linking the screening intervention to the surrogate) nor cite validated evidence that an increase in stage I–II detection alone translates into reduced CRC mortality. The authors acknowledge that the trial duration is too short to detect a net benefit in CRC incidence or mortality, and that the excess early-stage cancers may represent overdiagnosis.
“The duration of the trial is likely too short to detect a net benefit of the prevention in terms of a lower CRC incidence in the intervention arms compared to controls and/or to determine if a part of the early-stage CRC excess risk in the intervention arms…”
Find in source
02Treatment effect not shown to be clinically meaningful
highOverreachreviewer-assessedFull detail
The primary reported effect is an increase in stage I–II CRC detection (IRR 1.38 for colonoscopy, 1.19 for FIT), but the absolute rates are small (58.7 vs 42.5 per 100,000 person-years for colonoscopy) and the paper does not anchor this to a minimal clinically important difference or demonstrate that this translates into a meaningful clinical benefit. The authors note that the trial is underpowered for mortality and that the increase may represent overdiagnosis.
“The duration of the trial is likely too short to detect a net benefit of the prevention in terms of a lower CRC incidence in the intervention arms compared to controls and/or to determine if a part of the early-stage CRC excess risk in the intervention arms…”
Find in source

Findings by category

101ArithmeticNumerical inconsistencies 302OverreachOverstated conclusions 103AuthenticityData authenticity concerns 04DisclosureNone found 05AvailabilityNone found 06Copyedit6 minor suggestions

Numerical inconsistencies

1 finding · worst low

Internal contradictions in the reported numbersAssessed

Recomputed 2 tests: 2 consistent, 0 inconsistent; 2 via agent-written checks.

Overstated conclusions

3 findings · worst high

Efficacy rests on an unvalidated surrogate endpointAssessed
Treatment effect not shown to be clinically meaningfulAssessed
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.

Premise concern: surrogate not validated for clinical benefit; effect size not shown to be clinically meaningful.

Data authenticity concerns

1 finding · worst low

Other integrity concernAssessed

3 integrity concerns flagged (0 high).

Reporting gaps

None found

Checked — nothing surfaced.

Eight Dimensions8 pass

Sub-criteria

prior work citedADEQUATE

premise rationaleADEQUATE

limitations addressedADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

The paper establishes a clear scientific premise by citing prior research on CRC screening and identifying gaps in evidence, particularly the lack of RCTs comparing FIT to usual care.

Evidence

paraphrase[Main, paragraph 1]

“There are several trials of colonoscopy screening, but few have examined FIT compared to usual care.”

Main, paragraph 2Find in source

paraphrase[Discussion, paragraph 1]

“Paraphrase: The paper notes that other ongoing RCTs (COLONPREV, CONFIRM) lack a control arm, whereas SCREESCO includes a usual care control.”

PASSReviewer 2· 90% conf

The paper establishes a clear scientific premise by citing prior research on CRC screening and identifying the gap in evidence for FIT versus usual care.

Evidence

“The American College of Gastroenterology and the European Society of Gastrointestinal Endoscopy recommend CRC screening in individuals aged 50–75 years by colonoscopy or FIT”

Main, paragraph 1Find in source

“There are several trials of colonoscopy screening, but few have examined FIT compared to usual care”

Main, paragraph 2Find in source

paraphrase[Discussion, paragraph 1]

Sub-criteria

controlsADEQUATE

power analysisADEQUATE

blinding levelsADEQUATE

outlier handlingADEQUATE

randomization unitADEQUATE

inclusion exclusionADEQUATE

randomization methodADEQUATE

replicate distinctionN/A

independent replicationN/A

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 95% conf

The trial design is rigorous with clear randomization, pre-specified eligibility criteria, and a priori power calculations; blinding was not possible but is acknowledged.

Evidence

MethodsFind in source

“Masking was not possible due to the nature of the trial.”

MethodsFind in source

PASSReviewer 2· 95% conf

The trial design is rigorous with clear randomization, pre-specified eligibility, and power calculations, though blinding was not possible.

Evidence

MethodsFind in source

“Masking was not possible due to the nature of the trial.”

MethodsFind in source

Sub-criteria

demographicsADEQUATE

sex reportedADEQUATE

sex justifiedN/A

age weight healthADEQUATE

housing conditionsN/A

species strain sourceN/A

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

Biological variables are well reported for a human trial: sex, age, and demographics are detailed; species/strain and housing are not applicable.

Evidence

“Men | 15,550 | (50.0) | 93,309 | (50.0) | 30,128 | (50.0) | 60,261 | (50.0)”

Table 1Find in source

“assigned 278,280 individuals aged 60 years”

AbstractFind in source

paraphrase[Table 1]

“Educational level | Low | 5,704 | (18.3) | 34,378 | (18.4) | 11,569 | (19.2) | 23,134 | (19.2)”

PASSReviewer 2· 90% conf

Biological variables are well reported for a human trial, including sex, age, and demographics.

Evidence

“Men | 15,550 | (50.0) | 93,309 | (50.0) | 30,128 | (50.0) | 60,261 | (50.0)”

Table 1Find in source

“assigned 278,280 individuals aged 60 years”

AbstractFind in source

paraphrase[Table 1]

“Educational level | Low | 5,704 | (18.3) | 34,378 | (18.4) | 11,569 | (19.2) | 23,134 | (19.2)”

Sub-criteria

iacuc statementN/A

informed consentADEQUATE

irb ethics statementADEQUATE

regulatory complianceADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 95% conf

Ethical approvals are clearly documented with named committees and protocol numbers, and informed consent is described.

Evidence

“The Stockholm Ethics Committee approved the study (2012/2058-31/3) and the review of medical charts (2015/1958-2).”

MethodsFind in source

“All individuals invited for screening signed a written informed consent for the procedure and for biobanking of samples.”

MethodsFind in source

“The Swedish Ethical Review Authority waived the need for informed consent for accessing pseudonymized register-based data (2022/01946-02 and 2022/06863-2).”

MethodsFind in source

PASSReviewer 2· 95% conf

Ethical approvals and consent are clearly documented.

Evidence

“The Stockholm Ethics Committee approved the study (2012/2058-31/3)”

MethodsFind in source

“All individuals invited for screening signed a written informed consent for the procedure and for biobanking of samples.”

MethodsFind in source

“The Swedish Ethical Review Authority waived the need for informed consent for accessing pseudonymized register-based data (2022/01946-02 and 2022/06863-2).”

MethodsFind in source

Sub-criteria

mycoplasma testingN/A

reagents identifiedADEQUATE

organisms identifiedN/A

antibodies identifiedN/A

cell line authenticationN/A

software tools identifiedADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

The investigational product (FIT kit and colonoscopy) is identified with manufacturer and analyzer; software is identified with version and code repository.

Evidence

“One central laboratory performed all FIT analyses using a single OC-Sensor DIANA automated analyzer (Eiken Chemical).”

MethodsFind in source

“Stata version 13.1 and R version 4.0.2 were used for power calculations. Analyses were performed using R version 4.0.2.”

Statistical analysisFind in source

“The code was written in R version 4.0.2 using RStudio and is available at https://github.com/MarcusWesterberg/CRCs-and-AEs-during-diagnostic-phase-of-SCREESCO”

Data availabilityFind in source

PASSReviewer 2· 90% conf

Key resources are adequately identified, including the FIT analyzer and statistical software.

Evidence

“One central laboratory performed all FIT analyses using a single OC-Sensor DIANA automated analyzer (Eiken Chemical).”

MethodsFind in source

“Stata version 13.1 and R version 4.0.2 were used for power calculations. Analyses were performed using R version 4.0.2.”

Statistical analysisFind in source

Sub-criteria

tests namedADEQUATE

exact p valuesN/A

effect sizes ciADEQUATE

data presentationADEQUATE

software identifiedADEQUATE

assumptions verifiedADEQUATE

mathematical plausibilityN/A

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

Statistical methods are appropriate and well-described; effect sizes are reported with confidence intervals, and software is identified.

Evidence

“We compare each intervention arm with the corresponding control arm concerning each of the outcomes using incidence rates and IRRs using Poisson regression models with 95% CIs.”

Statistical analysisFind in source

“incidence rate ratio (IRR): 1.08, 95% confidence interval (CI): 0.91–1.28”

AbstractFind in source

“We assessed potential violations of equidispersion for each regression model and computed alternative CIs by use of robust standard errors.”

Statistical analysisFind in source

PASSReviewer 2· 90% conf

Statistical methods are appropriate and well reported, with effect sizes and confidence intervals.

Evidence

“We compare each intervention arm with the corresponding control arm concerning each of the outcomes using incidence rates and IRRs using Poisson regression models with 95% CIs.”

Statistical analysisFind in source

“We assessed potential violations of equidispersion for each regression model and computed alternative CIs by use of robust standard errors.”

Statistical analysisFind in source

“incidence rate ratio (IRR): 1.08, 95% confidence interval (CI): 0.91–1.28”

AbstractFind in source

Sub-criteria

code sharingADEQUATE

accession numbersN/A

repository depositN/A

data availability statementADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 95% conf

Data availability is clearly described with a managed-access mechanism, and code is shared in a public repository.

Evidence

Data availabilityFind in source

“The code was written in R version 4.0.2 using RStudio and is available at https://github.com/MarcusWesterberg/CRCs-and-AEs-during-diagnostic-phase-of-SCREESCO”

Data availabilityFind in source

PASSReviewer 2· 95% conf

Data availability is well described with a managed access process, and code is shared in a public repository.

Evidence

Data availabilityFind in source

“The code was written in R version 4.0.2 using RStudio and is available at https://github.com/MarcusWesterberg/CRCs-and-AEs-during-diagnostic-phase-of-SCREESCO”

Data availabilityFind in source

Sub-criteria

funding coiADEQUATE

trial registrationADEQUATE

reporting guidelineINADEQUATE

methods completenessADEQUATE

all outcomes reportedADEQUATE

limitations discussedADEQUATE

conclusions proportionalADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

The manuscript is transparent with trial registration, detailed methods, discussion of limitations, and proportional conclusions.

Evidence

“ClinicalTrials.gov: NCT02078804”

AbstractFind in source

“This study also has some limitations.”

Discussion ¶5Find in source

AcknowledgementsFind in source

PASSReviewer 2· 90% conf

Reporting is transparent with trial registration, protocol amendments, and limitations discussed.

Evidence

“ClinicalTrials.gov: NCT02078804”

AbstractFind in source

“This study also has some limitations.”

Discussion ¶5Find in source

AcknowledgementsFind in source

Registered (1 ID: ClinicalTrials.gov). No reporting guideline cited.

Broken references and links

None found

References 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.

Checked — nothing surfaced.

Checked 40 references by DOI: 1 verified — 39 no DOI (shown, not verified).

5 data/code links checked; 5 live.

Copyediting

6 minor

Wording, consistency and formatting errors that need correcting before submission.

No major wording or formatting errors. 6 minor suggestions below.

6 copyedit issues flagged: mostly consistency, typo, clarity.

Kaimen Rigor Action ItemsFinal pass before journal submission

1.
HIGHcopyedit
Correct the typo in Table 1: change '17,2738' to '172,738' in the 'Any prior cardiovascular or gastrointestinal event' row.
This is a clear numerical typo that could mislead readers and should be corrected via an erratum.
2.
HIGHreporting
Add an explicit statement of adherence to CONSORT (or another reporting guideline) in the Methods or a Reporting Summary.
Both reviewers noted the absence of an explicit reporting guideline statement, which is a standard expectation for RCTs and would enhance transparency.
3.
MEDIUMreporting
Clarify the discrepancy between the number randomized (31,140 in Methods) and the number analyzed (31,113) in the primary colonoscopy arm, and similarly for the FIT arm (60,300 vs 60,267).
The integrity check flagged these internal contradictions; explaining the exclusions will prevent reader confusion.
4.
MEDIUMreporting
Clarify the total number randomized (278,280) versus the number analyzed (278,051) in the abstract or methods.
The copyedit noted this inconsistency; a brief explanation of exclusions would improve clarity.
5.
MEDIUMstatistics
Clarify in the Methods whether robust standard errors were used in the final analysis or only as a sensitivity check.
The copyedit flagged this ambiguity; specifying the primary analysis approach is important for reproducibility.
6.
MEDIUMreporting
Consider reporting exact p-values for key comparisons in addition to confidence intervals, or note that they are available on request.
Both reviewers suggested this to facilitate meta-analyses and provide more complete statistical reporting.
7.
MEDIUMdata code
Provide a DOI or versioned release for the GitHub code repository to ensure permanent access.
Reviewer 2 suggested this to improve long-term reproducibility.
8.
LOWreporting
Add a note on the generalizability of findings to other age groups, as the study only included 60-year-olds.
Reviewer 2 noted this limitation; a brief statement would help readers interpret the applicability.
9.
LOWreporting
Consider discussing the higher rate of venous thromboembolism in the FIT arm (IRR 1.39) in the abstract or discussion.
The integrity check noted this finding is not discussed in the abstract; highlighting it would improve balance.
10.
LOWcopyedit
Rephrase the abstract sentence 'fecal immunochemical testing (FIT) compared with usual care with no screening' to 'compared with usual care (no screening)' for clarity.
Minor clarity improvement suggested by the copyedit pass.

Full text (58,708 chars)Analyzed: Aug 15, 2026