Ultraprocessed or minimally processed diets following healthy dietary guidelines on weight and cardiometabolic health: a randomized, crossover trial.
Dicken SJ, Jassil FC, Brown A, Kalis M, Stanley C, Ranson C, Ruwona T, Qamar S, Buck C, Mallik R, Hamid N, Bird JM, Brown A, Norton B, Gandini Wheeler-Kingshott CAM, Hamer M, van Tulleken C, Hall KD, Fisher A, Makaronidis J, Batterham RL
- DOI
- 10.1038/s41591-025-03842-0
- Record issued
- 2026-08-15
- 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/96f8f498-5964-4265-a18e-09ff66fb585f is authoritative.
How this rating was calculated
- StatisticsImpossible or misreported statistic−1★
- StatisticsStatistic did not reproduce−0.5★
- IntegrityIntegrity concern−0.5★
A demonstrable critical failure caps the rating at the minimum, regardless of the deductions above.
- The numeric-impossibility checks (GRIM/GRIMMER/DEBIT/SPRITE) did not run: 26 reported means were read, and their group size is not stated where the values are printed (this source has no machine-readable table structure). These checks need the count the mean was averaged over, so none was performed.
- 01Significance claim does not survive recomputationdemonstrable
Primary outcome p-value from mixed-effects model
“Δ%WC, −1.01% (s.e., 0.43; 95% CI, −1.87, −0.14; P = 0.024)”
- 02Printed percentage does not match its own count
40.1% does not match the reported count 55/135
“135 adults underwent screening, of whom 55 (40.1%) were eligible”
ResultsFind in source
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-designed and transparently reported randomized crossover feeding trial. The main methodological strength is the rigorous design with randomization, blinding, power calculation, and pre-specified outcomes. The primary concern is a statistical inconsistency in the primary outcome p-value that warrants verification.
Both reviewers agreed on study type (interventional) and on all dimensions except statistical analysis, where the deterministic verification introduced a new finding. Bench-science criteria (cell lines, antibodies, etc.) were not applicable. The statistics verification covered only 2 tests; the rest were not machine-verifiable.
Numerical inconsistencies
2 findings · worst highValues 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.
- Summary statistic impossible for the stated N (GRIM/GRIMMER)Recomputed
- Internal contradictions in the reported numbersAssessed
Recomputed 1 test: 0 consistent, 1 inconsistent (1 change significance at p<.05); 1 via agent-written checks. 1 reported summary statistic mathematically impossible for the stated N (PERCENT).
- PERCENT40.1% does not match the reported count 55/135
“135 adults underwent screening, of whom 55 (40.1%) were eligible”
ResultsFind in source
- lowinternal contradictionThe abstract states '28 people were randomized to MPF then UPF, and 27 to UPF then MPF; 50 participants comprised the intention-to-treat sample.' The results section states 'Six participants withdrew during the first-period MPF diet (sequence MPF/UPF), two during washout (sequence MPF/UPF) and four during the second-period MPF diet (sequence UPF/MPF).' This sums to 12 withdrawals, but the ITT sample is 50, implying 5 withdrawals from the 55 randomized. The discrepancy may be due to participants who withdrew but still provided primary outcome data, but this is not explicitly clarified.
“Six participants withdrew during the first-period MPF diet (sequence MPF/UPF), two during washout (sequence MPF/UPF) and four during the second-period MPF diet (sequence UPF/MPF).”
AbstractFind in source
Overstated conclusions
1 finding · worst criticalConclusions 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.
- Significance claim flips when recomputedRecomputed
- SIGNIFICANCE OVERSTATEDINCONSISTENTreported p = .024 · recomputed p = .669Reviewers 1, 2Primary outcome p-value from mixed-effects modelReported as statistically significant, but recomputing from the paper’s own numbers gives p ≥ 0.05 — the result may not be significant as claimed.
“Δ%WC, −1.01% (s.e., 0.43; 95% CI, −1.87, −0.14; P = 0.024)”
Taken as given: The reported s.e. is the standard error of the difference.; The degrees of freedom is 46.1 as reported in Figure 2.; The test is two-sided.Method: Two-sided t-test using the reported standard error and degrees of freedom.How we recomputed it: pT(0.43, 46.1)
9 major claims checked against the paper's own evidence: all adequately supported.
- supportedReviewers 1, 2Minimally processed diets lead to greater weight loss than ultraprocessed diets following UK healthy eating guidelines.The primary outcome analysis shows a statistically significant difference in %WC favoring MPF, with a p-value of 0.024 and a 95% CI excluding zero.Evidence: Primary outcome: Δ%WC, −1.01% (95% CI, −1.87, −0.14; P = 0.024).
“Findings indicate greater weight loss on MPF than UPF diets”
AbstractFind in source - supportedReviewer 1The UPF diet following UK dietary guidance resulted in weight loss.The UPF diet showed a significant weight loss from baseline, with %WC of −1.05% (95% CI, −1.98, −0.13).Evidence: Primary outcome: UPF %WC, −1.05% (95% CI, −1.98, −0.13).
“UPF, −1.05% (95% CI, −1.98, −0.13)”
ResultsFind in source - supportedReviewer 1The greater weight loss on MPF was through greater reductions in fat mass and total body water mass.The secondary outcomes show significantly greater reductions in fat mass and total body water mass on MPF, with no significant difference in fat-free mass.Evidence: Secondary outcomes: fat mass difference −0.98 kg (P=0.004), total body water mass difference −0.51 kg (P=0.002), fat-free mass difference 0.00 kg (P=0.993).
“We observed that the greater weight loss on the MPF diet was through greater reductions in fat mass and total body water mass, with no significant differences in fat-free mass change between diets.”
DiscussionFind in source - supportedReviewer 1The UPF diet led to reductions in several cardiometabolic risk factors including HR, fasting glucose, cholesterol and LDL-C.The results show significant reductions from baseline on the UPF diet for HR, fasting glucose, total cholesterol, and LDL-C.Evidence: Secondary outcomes: HR −4.35 (95% CI, −8.28, −0.42), fasting glucose −0.19 (95% CI, −0.32, −0.06), total cholesterol −0.44 (95% CI, −0.63, −0.24), LDL-C −0.38 (95% CI, −0.54, −0.22).
“whereas fasting glucose and low-density lipoprotein cholesterol (LDL-C) were significantly lower at 8 weeks compared with baseline on the UPF diet only.”
ResultsFind in source - supportedReviewers 1, 2The findings highlight the importance of food processing in public health policy and dietary guidance.The study demonstrates a significant difference in weight loss between MPF and UPF diets within the context of dietary guidelines, supporting the claim that food processing matters beyond nutrient content.Evidence: Primary outcome and discussion of implications.
“These findings highlight the importance of food processing in public health policy and dietary guidance in addition to existing recommendations.”
DiscussionFind in source - supportedReviewer 2Both MPF and UPF diets following UK dietary guidance result in weight loss.Both diets show significant weight loss from baseline, as reported in the primary outcome analysis.Evidence: MPF %WC −2.06% (95% CI, −2.99, −1.13); UPF %WC −1.05% (95% CI, −1.98, −0.13).
“In the ITT analysis, %WC at 8 weeks was significantly lower on both diets (MPF, −2.06% ((95% confidence interval (CI), −2.99, −1.13); UPF, −1.05% (95% CI, −1.98, −0.13))”
ResultsFind in source - supportedReviewer 2The UPF diet did not result in significant fat loss.The results show no significant reductions in fat mass, body fat percentage, or visceral fat rating on the UPF diet, while MPF showed significant reductions.Evidence: Table 2: Fat mass change on UPF: −0.61 (95% CI, −1.34, 0.12), not significant.
“Fat mass, body fat percentage, visceral fat rating and total body water mass were significantly lower at 8 weeks from baseline on the MPF but not UPF diet.”
ResultsFind in source - supportedReviewer 2The greater weight loss on MPF is due to greater reductions in fat mass and total body water mass.The results show significantly greater reductions in fat mass and total body water mass on MPF compared to UPF, with no significant difference in fat-free mass.Evidence: Table 2: Fat mass difference −0.98 kg (P=0.004); total body water mass difference −0.51 kg (P=0.002).
“Reductions in fat mass (−0.98 kg (s.e., 0.32); P = 0.004), body fat percentage (−0.76% (s.e., 0.28); P = 0.010), visceral fat rating (−0.41 (s.e., 0.15); P = 0.008) and total body water mass (−0.51 kg (s.e., 0.15); P = 0.002) were significantly greater on the MPF compared with UPF diet.”
ResultsFind in source - supportedReviewer 2The UPF diet led to reductions in several cardiometabolic risk factors including LDL-C.The results show significant reductions in LDL-C on the UPF diet, and the difference between diets favored UPF.Evidence: Table 2: LDL-C change on UPF: −0.38 (95% CI, −0.54, −0.22); difference between diets: 0.25 (P=0.016).
“Changes in triglycerides were significantly lower on the MPF than UPF diet (−0.25 mmol l −1 (s.e., 0.08); P = 0.004), whereas changes in LDL-C were significantly lower on the UPF than MPF diet (0.25 mmol l −1 (s.e., 0.10); P = 0.016).”
ResultsFind in source
Efficacy claim is anchored to an adequate endpoint and a meaningful effect.
- ADEQUATESurrogate endpointThe primary outcome is percentage weight change, which is a hard clinical outcome directly relevant to obesity. Weight change is a validated clinical endpoint, not a surrogate biomarker. The trial also reports secondary outcomes like body composition and cardiometabolic markers, but the primary efficacy claim is based on weight loss, which is clinically meaningful.
“The primary outcome was the within-participant difference in percent weight change (%WC) between diets, from baseline to week 8.”
- ADEQUATEEffect sizeThe effect size is a 1.01% greater weight loss on the MPF diet compared to UPF, with a Cohen's d of -0.48, indicating a moderate effect. The paper discusses clinical significance, noting that clinically significant weight loss is related to favorable changes in cardiometabolic risk factors, and the observed difference is statistically significant. The effect is anchored to clinical meaningfulness in the context of weight management.
“MPF (%WC, −2.06 (95% confidence interval (CI), −2.99, −1.13) and UPF (%WC, −1.05 (95% CI, −1.98, −0.13)) resulted in weight loss, with significantly greater %WC on MPF (Δ%WC, −1.01 (95% CI, −1.87, −0.14), P = 0.024; Cohen’s d , −0.48 (95% CI, −0.91, −0.06)).”
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 research on UPF and health outcomes, including two prior RCTs, and identifies the gap of no trials within dietary guidelines context. The rationale for the study is clearly stated, and the hypothesis follows from the cited evidence. Limitations of prior research (e.g., lack of context of dietary guidelines) are addressed by the study design.
“To date, two RCTs demonstrate unfavorable weight changes on UPF compared with MPF diets matched for presented energy and nutrients”
“no RCTs have assessed the health impact of food processing in the context of dietary guidance.”
“Higher UPF intakes are associated with increased risks of obesity , cardiometabolic disease, and all-cause mortality”
“Therefore, ‘Ultra processed versus minimally processed diets following UK dietary guidance on health outcomes’ (UPDATE)—a single-center, community-based, 2 × 2 crossover RCT—aimed to compare the health effects between 8-week MPF and UPF diets following EWG recommendations”
The trial is a randomized crossover design with block randomization stratified by nightshift status, sex, and ethnicity. Participants were blinded to the primary outcome and diet group labels. A power calculation was performed, and inclusion/exclusion criteria were prespecified. The analysis population (ITT and PP) and handling of missing data are clearly defined. The study is a human RCT, so some bench-science criteria are not applicable.
“Participants were not informed of the processing groups of the diets.”
“Participants were block randomized by the research team using Sealed Envelope ( https://www.sealedenvelope.com ) to either (1) the MPF diet then UPF diet ( n = 28), or (2) the UPF diet then MPF diet ( n = 27).”
“Participants were not informed of the processing groups of the diets. All participant communications omitted the terms MPF or UPF, with diets being referred to as Diet A or Diet B.”
“In total, 44 participants were required to detect a mean difference of 2.7% WC between groups, assuming weight loss on the MPF diet and no WC on the UPF diet, with a s.d. of the mean difference of 5.4% (power, 0.9; alpha, 0.05; two-sided paired t -test, SPSS v.27.0).”
Sex is reported (90.9% female), age, weight, BMI, and health status are provided. Demographics include ethnicity, occupation, education, and marital status. Since both sexes are enrolled, sex justification is not applicable. Species/strain and housing conditions are not applicable for a human trial.
“Mean age was 43.2 years (s.e., 1.5), 36 (65.5%) were of white ethnicity, 50 (90.9%) were female”
“Table 1 Baseline demographic and clinical characteristics overall and by randomization arm”
“Mean age was 43.2 years (s.e., 1.5), 36 (65.5%) were of white ethnicity, 50 (90.9%) were female”
“Mean weight was 89.4 kg (s.e., 1.7), and body mass index (BMI) 32.7 kg m −2 (s.e., 0.5).”
“Table 1 Baseline demographic and clinical characteristics overall and by randomization arm”
The trial was approved by the Yorkshire and The Humber–Sheffield Research Ethics Committee on 22 December 2022 (22/YH/0281). Written informed consent was obtained from all participants. The study was registered on ClinicalTrials.gov. Regulatory compliance is implied by adherence to CONSORT and SPIRIT guidelines.
“The Yorkshire and The Humber–Sheffield Research Ethics Committee approved the trial on 22 December 2022 (22/YH/0281).”
“All participants provided written informed consent before any screening or research-associated measurement.”
“The Yorkshire and The Humber–Sheffield Research Ethics Committee approved the trial on 22 December 2022 (22/YH/0281).”
“Written informed consent was obtained before any screening or research-associated measurement.”
“The study was registered prospectively on ClinicalTrials.gov ( NCT05627570 (https://clinicaltrials.gov/ct2/show/NCT05627570) ).”
The investigational products (MPF and UPF diets) are described in detail, including sourcing from UK supermarkets and matching to EWG recommendations. Software used for randomization (Sealed Envelope), dietary assessment (Intake24), and analysis (R, SPSS, Prism) are identified with versions. Measurement devices (Tanita scale, ActiGraph) are named. Antibodies, cell lines, and mycoplasma testing are not applicable.
“Participants were provided with an 8-week MPF diet and an 8-week UPF diet, both following EWG recommendations”
“Analyses were conducted in R v.2024.04.1+748. Data were presented in tabular form using Microsoft Excel v.16.91 (24111020), figures were created using Prism 10 v.10.2.3.”
“Weight was measured using an electronic scale to the nearest 0.1 kg (Tanita DC-430MAS; Tanita).”
“Participants were provided with an 8-week MPF diet and an 8-week UPF diet, both following EWG recommendations, in a random order, with a 4-week washout period.”
“Analyses were conducted in R v.2024.04.1+748. Data were presented in tabular form using Microsoft Excel v.16.91 (24111020), figures were created using Prism 10 v.10.2.3.”
“Participants were block randomized by the research team using Sealed Envelope ( https://www.sealedenvelope.com )”
Mixed-effects models are described with assumptions checked visually. Exact p-values are reported (e.g., P = 0.024). Effect sizes with 95% CIs are provided (e.g., Cohen's d). Statistical software is identified. Data presentation includes individual data points in figures and per-group n. Mathematical plausibility checks were not possible for all values due to model-derived estimates, but no inconsistencies were found.
“Mixed-effects models were used in an ITT analysis to assess the difference in %WC at 8 weeks and secondary outcomes”
“Δ%WC, −1.01% (s.e., 0.43; 95% CI, −1.87, −0.14; P = 0.024)”
“Mixed-effects models were used in an ITT analysis to assess the difference in %WC at 8 weeks and secondary outcomes, with a random effect for participants, and adjusting for randomization arm (including interaction with diet) and nightshift status.”
“Within-participant differences in %WC were significantly greater on the MPF versus UPF diet (Δ%WC, −1.01% (s.e., 0.43; 95% CI, −1.87, −0.14; P = 0.024).”
“Mixed-effects model assumptions including normality of residuals and homoscedasticity were checked visually and verified.”
The data availability statement provides a clear mechanism for requesting data from the corresponding author, with a timeline. Code is available on GitHub without restriction. Since data are individual-level and anonymized, repository deposit and accession numbers are not applicable.
“Data access requests should first contact the corresponding author (samuel.dicken.20@ucl.ac.uk) to discuss data of interest and to obtain approval.”
“Code for the analysis is publicly available and available without restriction via GitHub at https://github.com/SamuelJDicken/UPDATE”
“Data access requests should first contact the corresponding author (samuel.dicken.20@ucl.ac.uk) to discuss data of interest and to obtain approval. Data for all outcomes in this paper can be requested. Data will be anonymized and provided in summary format (not individual-level data) before sharing to meet UK General Data Protection Regulation requirements. The timeline between requesting data and approval of data requests is 3 months. Data will be provided within 3 months of approval.”
“Code for the analysis is publicly available and available without restriction via GitHub at https://github.com/SamuelJDicken/UPDATE .”
The paper follows CONSORT guidelines and is registered on ClinicalTrials.gov. Methods are detailed enough for replication. All prespecified outcomes are reported, including null results. Limitations are thoroughly discussed. Conclusions are proportional to the evidence. Funding and competing interests are disclosed.
“reporting was according to the Consolidated Standards of Reporting Trials (CONSORT)”
“Limitations include that a potential carryover effect cannot be ruled out.”
“The study was registered prospectively on ClinicalTrials.gov ( NCT05627570 (https://clinicaltrials.gov/ct2/show/NCT05627570) ).”
“Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines were used to design the protocol, and reporting was according to the Consolidated Standards of Reporting Trials (CONSORT) .”
“Limitations include that a potential carryover effect cannot be ruled out. However, the washout period helped minimize this.”
Registered (1 ID: ClinicalTrials.gov). Reporting guidelines cited: CONSORT, SPIRIT.
Broken references and links
None foundReferences 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 63 references by DOI: 45 verified — 18 no DOI (shown, not verified).
- NO DOIThe role of diet quality in mediating the association between ultra-processed food intake, obesity and health-related outcomes: a review of prospective cohort studiesNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIDietary Guidelines for the Brazilian PopulationNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIReport of the Commission on Ending Childhood ObesityNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIPart 3: Adult Overweight and Obesity. Statistics on Obesity, Physical Activity and Diet, England, 2020No DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIDoes the concept of ‘ultra-processed foods’ help inform dietary guidelines, beyond conventional classification systems? Debate consensusNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIGovernment Recommendations for Energy and Nutrients for Males and Females Aged 1–18 Years and 19+ YearsNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIThe Eatwell GuideNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOISACN Statement on Processed Foods and HealthNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIDietary Guidelines for Americans. 2025 Dietary Guidelines Advisory Committee: Meeting 5No DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIAssociation between eating rate and obesity: a systematic review and meta-analysisNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIBody Weight PlannerNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIRecipe for Health: a Plan to Fix our Broken Food SystemNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIDietary adherence to long-term controlled feeding in a calorie-restriction study in overweight men and womenNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOINDNS: results from years 9 to 11 (2016 to 2017 and 2018 to 2019)No DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIAlcohol Consumption: Advice on Low Risk DrinkingNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIEvaluating the Power of Food Scale in obese subjects and a general sample of individuals: development and measurement propertiesNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIStatistical Power Analysis for the Behavioral SciencesNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
- NO DOIThe relationship between shift work and metabolic risk factors: a systematic review of longitudinal studiesNo DOI in the reference — shown for manual review; not independently verifiable (not a fabrication signal).
3 data/code links checked; 3 live.
- datahttps://clinicaltrials.gov/study/NCT05627570LIVEHTTP 200Resolves, but the content could not be matched to the paper.
- datahttps://clinicaltrials.gov/ct2/show/NCT05627570LIVEHTTP 200Resolves, but the content could not be matched to the paper.
- codeGitHubLIVEHTTP 200https://github.com/SamuelJDicken/UPDATEResolves to GitHub (code repository).
Copyediting
6 minorWording, 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, clarity, grammar.
- MINORconsistencyAbstract“Clinicaltrials.gov registration: NCT05627570”→ Change to 'ClinicalTrials.gov' for consistency.Capitalization inconsistency.
- MINORclarityResults, Participant disposition“Six participants withdrew during the first-period MPF diet (sequence MPF/UPF), two during washout (sequence MPF/UPF) and four during the second-period MPF diet (sequence UPF/MPF).”→ Clarify that the four withdrawals during second-period MPF diet are from the UPF/MPF sequence.The sentence is slightly confusing but understandable.
- MINORconsistencyTable 1“BMI 25–29.9 kg m−2 18 (33%)”→ Use consistent decimal places (e.g., 33.0%) or round consistently.Percentages are rounded inconsistently.
- MINORgrammarDiscussion“These findings highlight the benefit of following UK dietary recommendations.”→ Consider 'These findings highlight the benefits of following UK dietary recommendations.'Minor grammatical issue.
- MINORconsistencyAbstract“Clinicaltrials.gov registration: NCT05627570”→ Change to 'ClinicalTrials.gov' for consistency with the rest of the text.Inconsistent capitalization of 'ClinicalTrials.gov'.
- MINORclarityResults, Participant disposition“Six participants withdrew during the first-period MPF diet (sequence MPF/UPF), two during washout (sequence MPF/UPF) and four during the second-period MPF diet (sequence UPF/MPF).”→ Clarify that the four withdrawals during the second-period MPF diet are from the UPF/MPF sequence.The sentence is slightly confusing but understandable.
The published work is largely robust, but the inconsistency in the primary outcome p-value is a validity concern that an informed reader should weigh. An erratum or independent re-analysis of the primary analysis is warranted to confirm the reported effect.
- 1.CRITICALstatisticsResolve the statistics inconsistency that flips a significance claim: Recomputed 1 test: 0 consistent, 1 inconsistent (1 change significance at p<.05); 1 via agent-written checks. 1 reported summary statistic mathematically impossible for the stated N (PERCENT).Demonstrable critical failure — blocks the verdict from passing.
- 2.HIGHstatisticsRe-analyze the primary outcome (Δ%WC) and verify the reported p-value (0.024) against the recomputed value (0.669); if the recomputation is correct, issue a correction to the abstract, results, and conclusions.The primary outcome p-value is inconsistent with the recomputed value, which could invalidate the headline finding.
- 3.HIGHreportingClarify the discrepancy between the 12 withdrawals described in the results and the ITT sample of 50 from 55 randomized; specify how many participants provided primary outcome data despite withdrawing.The internal contradiction in participant numbers could confuse readers and undermine trust in the analysis.
- 4.HIGHreportingReport the exact p-values for all secondary outcomes in the main text, not just in tables, and specify how multiple comparisons were handled.Threshold-only p-values and lack of multiplicity adjustment details reduce transparency and reproducibility.
- 5.HIGHreportingProvide a CONSORT flow diagram in the main text (or clearly reference it as Figure 1b) to show participant flow through each diet period.A flow diagram improves transparency and helps readers understand the withdrawal pattern.
- 6.MEDIUMreportingAdd a sensitivity analysis excluding participants with low adherence to assess robustness of the primary finding.Sensitivity analyses strengthen confidence in the results, especially given the statistical inconsistency.
- 7.MEDIUMreportingDiscuss the potential impact of the high proportion of female participants (90.9%) on generalizability of the findings.The skewed sex distribution may limit applicability to male populations.
- 8.MEDIUMreportingReport the washout period length (4 weeks) and its justification in the abstract.The washout period is critical for crossover design validity and should be highlighted.
- 9.MEDIUMdata codeConsider depositing anonymized individual-level data in a public repository with a DOI, while respecting privacy constraints.Providing individual-level data would enhance reproducibility and allow independent verification of the primary analysis.
- 10.MEDIUMreportingAdd a statement on the absence of a Data Safety Monitoring Board in the methods.Transparency about oversight is important for a dietary intervention trial.
- 11.LOWcopyeditFix the capitalization of 'ClinicalTrials.gov' in the abstract (currently 'Clinicaltrials.gov').Consistency in terminology is expected in a published manuscript.
- 12.LOWcopyeditClarify the sentence in Results, Participant disposition, that the four withdrawals during the second-period MPF diet are from the UPF/MPF sequence.The current wording is slightly confusing and could be misinterpreted.
- 13.LOWcopyeditStandardize decimal places in Table 1 percentages (e.g., 33% vs 33.0%).Inconsistent rounding is a minor but noticeable formatting issue.
- 14.LOWcopyeditChange 'These findings highlight the benefit' to 'These findings highlight the benefits' in the Discussion.Minor grammatical correction for clarity.
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.