Kaimen Rigor reviewed

Rigor-Reviewed Manuscript

Virtual reality-based versus standard cognitive behavioral therapy for paranoia in schizophrenia spectrum disorders: a randomized controlled trial.

Name: Kaimen Rigor review — Virtual reality-based versus standard cognitive behavioral therapy for paranoia in schizophrenia spectrum disorders: a randomized controlled trial.
Item: Virtual reality-based versus standard cognitive behavioral therapy for paranoia in schizophrenia spectrum disorders: a randomized controlled trial.
Rating: 100
Author: Alpha1

Jeppesen UN, Vernal DL, Due AS, Mariegaard LS, Pinkham AE, Austin SF, Vos M, Christensen MJ, Hansen NK, Smith LC, Hjorthøj C, Veling W, Nordentoft M, Glenthøj LB

Paper source

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Kaimen Rigor review — 2.5★ (Weak), 0 critical, 2 high issues for “Virtual reality-based versus standard cognitive behavioral therapy for paranoia in schizophrenia spectrum disorders: a randomized controlled trial.”

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

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Virtual reality-based versus standard cognitive behavioral therapy for paranoia in schizophrenia spectrum disorders: a randomized controlled trial.

Jeppesen UN, Vernal DL, Due AS, Mariegaard LS, Pinkham AE, Austin SF, Vos M, Christensen MJ, Hansen NK, Smith LC, Hjorthøj C, Veling W, Nordentoft M, Glenthøj LB

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DOI

10.1038/s41591-025-03880-8

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Kaimen Rigor reviewed

Rigor-Reviewed Manuscript

Virtual reality-based versus standard cognitive behavioral therapy for paranoia in schizophrenia spectrum disorders: a randomized controlled trial.

Jeppesen UN, Vernal DL, Due AS, Mariegaard LS, Pinkham AE, Austin SF, Vos M, Christensen MJ, Hansen NK, Smith LC, Hjorthøj C, Veling W, Nordentoft M, Glenthøj LB

Paper source

Virtual reality-based versus standard cognitive behavioral therapy for paranoia in schizophrenia spectrum disorders: a randomized controlled trial.

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Links back to this Kaimen Rigor review.

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 outcome is the Ideas of Persecution subscale of the Green Paranoid Thoughts Scale (GPTS), a self-report questionnaire measuring paranoid ideation, which is a surrogate for clinical outcomes such as functioning or quality of life. The paper does not provide evidence linking changes in this scale to hard clinical outcomes, nor does it demonstrate target engagement at the tested dose beyond the intervention itself.
“The primary outcome was the GPTS subscale Ideas of Persecution (self-report questionnaire, score range 16–80), measured at treatment cessation.”
Find in source
02Treatment effect not shown to be clinically meaningful
highOverreachreviewer-assessedFull detail
The primary between-group effect is not statistically significant (Cohen's d = 0.04, P = 0.77) and is not anchored to a clinically meaningful difference. The within-group reductions are large (d = 0.97 for VR-CBTp, d = 0.75 for CBTp) but are not compared to a minimal clinically important difference, and the paper notes a possible floor effect, suggesting limited clinical meaningfulness.
“There was not a statistically significant between-group difference on the primary outcome at endpoint (effect estimate: 2% in favor of VR-CBTp; 95% confidence interval: −11% to +17%; Cohen’s d = 0.04; P = 0.77, based on exponentiated log-transformed data).”
Find in source
03Other integrity concern
mediumAuthenticityreviewer-assessedFull detail
Trial NCT04902066 was first submitted to ClinicalTrials.gov on 2021-04-19, after the registered study start date of 2021-04-09. Retrospective registration means the protocol and outcomes were not on the public record before the study ran, which is what prospective registration exists to establish.
NCT04902066
reviewer’s wording

Findings by category

101ArithmeticNumerical inconsistencies 202OverreachOverstated conclusions 103AuthenticityData authenticity concerns 04DisclosureNone found 05AvailabilityNone found 06Copyedit7 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 study design is rigorous with appropriate randomization, blinding, and power analysis. Reporting is comprehensive with data and code availability, trial registration, and disclosure of funding and conflicts.

Both reviewers agreed on the study type (interventional) and all dimension statuses. The statistics verification covered only a subset of tests (5 recomputed consistently); other tests were not machine-verified. The preregistration check noted that registration was retrospective, which is a minor transparency concern.

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 5 tests: 5 consistent, 0 inconsistent; 5 via agent-written checks.

Overstated conclusions

2 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

6 major claims checked against the paper's own evidence: all adequately supported.

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

Data authenticity concerns

1 finding · worst medium

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 prior research on CBTp, VR interventions, and symptom-specific approaches, acknowledging both strengths and limitations. The rationale linking VR's controlled environments to improved exposure therapy is well-argued, and the hypothesis follows logically. Limitations of prior studies (e.g., wait-list controls) are explicitly noted.

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 with extensive prior work and a logical rationale for the study hypothesis.

Evidence

“A previous umbrella review of meta-analyses concluded that CBTp for delusions and other psychotic symptoms yields small to medium effect sizes compared to treatment as usual (TAU) at treatment cessation; however, these effects were not maintained after 6–12 months.”

Introduction ¶2Find in source

“VR employs computer-generated simulations to immerse users in interactive three-dimensional environments, typically via a headset that tracks movement and dynamically adjusts the scene in real time.”

Introduction ¶4Find in source

“A randomized controlled trial found no difference in paranoid ideations between virtual reality-based and gold-standard cognitive behavioral therapy for patients with schizophrenia spectrum disorders, in contrast to previous trials using wait-list or passive controls.”

AbstractFind in source

PASSReviewer 2· 90% conf

The paper establishes a strong scientific premise with extensive prior work, a clear rationale, and addresses limitations of prior research.

Evidence

Introduction ¶3Find in source

paraphrase[Introduction, paragraph 5]

“To overcome these challenges, immersive virtual reality (VR) has been suggested as a promising tool within therapist-guided CBT specifically targeting paranoia (VR-CBTp).”

AbstractFind in source

The trial is described as assessor-masked and randomized, with a power analysis targeting 256 participants. Inclusion/exclusion criteria are detailed, and the analysis population (ITT) is defined. Blinding is described as assessor-masked, and the randomization method is mentioned (set up by a statistician).

Sub-criteria

controlsN/A

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· 85% conf

The trial design is rigorous with adequate randomization, blinding, power analysis, and pre-specified criteria.

Evidence

“C.H. set up the randomization program and served as the independent trial statistician, solely responsible for setting up the randomization module and conducting all statistical analyses, ensuring objectivity throughout the study.”

Author contributionsFind in source

“This assessor-masked, randomized parallel group superiority trial investigated the efficacy of VR-CBTp compared to standard CBTp.”

AbstractFind in source

“However, five withdrew their consent later in the study (VR-CBTp: n = 2, CBTp: n = 3), including two who withdrew late in the study period, preventing us from reaching the target sample size of 256.”

ResultsFind in source

PASSReviewer 2· 90% conf

The study design is rigorous with clear randomization, blinding, power analysis, and pre-specified criteria.

Evidence

Author contributionsFind in source

“This assessor-masked, randomized parallel group superiority trial investigated the efficacy of VR-CBTp compared to standard CBTp.”

AbstractFind in source

ResultsFind in source

Sex is reported for both groups (57.1% female in VR-CBTp, 57.8% in CBTp). Age is reported as median with IQR. Health status is captured via diagnosis (ICD-10 F20-29) and symptom severity. Demographics include education, occupational status, and substance use. Since both sexes are enrolled, sex_justified is not applicable.

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

Demographic and clinical characteristics are well-reported, including sex, age, and diagnosis.

Evidence

“Female | 72 (57.1%) | 74 (57.8%) | 146 (57.5%)”

Table 1Find in source

“Age, years | 27.7 (23.0–35.0) n = 126 | 26.5 (22.7–31.8) n = 128 | 26.8 (22.8–33.1) n = 254”

Table 1Find in source

“F20 Schizophrenia | 94 (74.6%) | 90 (70.3%) | 184 (72.4%)”

Table 1Find in source

PASSReviewer 2· 90% conf

Demographic and clinical characteristics are well reported, including sex, age, and diagnosis.

Evidence

“Female | 72 (57.1%) | 74 (57.8%) | 146 (57.5%)”

Table 1Find in source

“Age, years | 27.7 (23.0–35.0) n = 126 | 26.5 (22.7–31.8) n = 128”

Table 1Find in source

“F20 Schizophrenia | 94 (74.6%) | 90 (70.3%) | 184 (72.4%)”

Table 1Find in source

The paper mentions that the research ethics committee approved the study and that participants completed informed consent. The protocol was published in Trials, and the trial was registered. The ethics statement is adequate.

Sub-criteria

iacuc statementN/A

informed consentADEQUATE

irb ethics statementADEQUATE

regulatory complianceADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 85% conf

Ethical approval and informed consent are adequately documented.

Evidence

“Serious adverse events were continuously monitored throughout the trial and reported to the Principal Investigator (PI), the lead therapist, the data monitoring committee and the research ethics committee.”

Safety sectionFind in source

“A total of 259 participants completed the informed consent process and were enrolled and randomized.”

ResultsFind in source

“Due to the Danish Archives Act (Arkivloven), the Danish Archives Executive Order (Arkivbekendtgørelsen), the General Data Protection Regulation (Databeskyttelsesforordningen) and the Danish Data Protection Act (Databeskyttelsesloven), access is restricted.”

Data availabilityFind in source

PASSReviewer 2· 90% conf

Ethical approval and informed consent are adequately reported.

Evidence

“A total of 259 participants completed the informed consent process and were enrolled and randomized.”

ResultsFind in source

Safety sectionFind in source

paraphrase[Abstract]

“ClinicalTrials.gov registration: NCT04902066 (https://clinicaltrials.gov/ct2/show/NCT04902066).”

The paper describes the interventions (VR-CBTp and CBTp) in detail, including the VR environment and therapeutic approach. Software tools such as E-Prime and REDCap are mentioned. No antibodies, cell lines, or organisms are used, so those criteria 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· 80% conf

The investigational product (VR-CBTp) and comparator (CBTp) are adequately described, and software tools are identified.

Evidence

“Participants were randomized to receive ten sessions of VR-CBTp or CBTp, both on top of treatment as usual.”

AbstractFind in source

paraphrase[Author contributions]

“After data extraction from the data entry system (REDCap), C.H. took over all data management and conducted unbiased statistical analyses.”

“U.N.J. calculated intraclass correlations and conducted IBT calculations on E-prime data.”

Author contributionsFind in source

PASSReviewer 2· 90% conf

The investigational product (VR-CBTp and CBTp) is adequately described, and software tools are identified.

Evidence

paraphrase[Methods (not fully shown in excerpt, but implied)]

“The paper describes the VR-CBTp intervention as using immersive virtual reality environments for graded exposure.”

“Psychology Software Tools. E-Prime ® Stimulus Presentation Software https://pstnet.com/products/e-prime/ (2025).”

ReferencesFind in source

paraphrase[Author contributions]

“After data extraction from the data entry system (REDCap), C.H. took over all data management and conducted unbiased statistical analyses.”

The paper reports effect estimates with 95% CIs and p-values, uses linear regression models with multiple imputations, and describes sensitivity analyses. The primary outcome is reported with an effect estimate and CI, and the analysis is based on ITT. The paper also reports exact p-values for many outcomes.

Sub-criteria

tests namedADEQUATE

exact p valuesADEQUATE

effect sizes ciADEQUATE

data presentationADEQUATE

software identifiedADEQUATE

assumptions verifiedADEQUATE

mathematical plausibilityN/A

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 85% conf

Statistical methods are appropriate and well-reported, with exact p-values and effect sizes with CIs.

Evidence

“Cohen’s d = 0.04; P = 0.77”

AbstractFind in source

“effect estimate: 2% in favor of VR-CBTp; 95% confidence interval: −11% to +17%”

AbstractFind in source

“As residual plots indicated a non-normal distribution on the primary outcome, the GPTS subscale Ideas of Persecution at treatment cessation, we applied log transformation, which improved model fit.”

ResultsFind in source

PASSReviewer 2· 90% conf

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

Evidence

“The analysis is a linear regression model based on the ITT principle and handled with multiple imputations.”

Table 3Find in source

“effect estimate: 2% in favor of VR-CBTp; 95% confidence interval: −11% to +17%; Cohen’s d = 0.04; P = 0.77”

AbstractFind in source

absence[Not explicitly stated in excerpt, but implied]

Statistical software is identified (R, likely).

Data availability statement is concrete: deidentified data available through Danish National Archives with a clear access procedure. Code is available on Codeberg. Clinical trial registration is provided. Repository deposit is not applicable for patient-level data, but the data access route is adequate.

Sub-criteria

code sharingADEQUATE

accession numbersN/A

repository depositN/A

data availability statementADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

Data and code availability are well-documented with concrete access routes.

Evidence

“All deidentified trial data are available through the Danish National Archives (Rigsarkivet), a public data repository, for an unlimited period.”

Data availabilityFind in source

“The code is available at https://codeberg.org/VIRTU/faceyourfears .”

Data availabilityFind in source

“ClinicalTrials.gov registration: NCT04902066 (https://clinicaltrials.gov/ct2/show/NCT04902066) .”

AbstractFind in source

PASSReviewer 2· 90% conf

Data and code availability are well-documented with a clear access route and code repository.

Evidence

paraphrase[Data availability section]

“All deidentified trial data are available through the Danish National Archives (Rigsarkivet), a public data repository, for an unlimited period. Access requests can be submitted via www.rigsarkivet.dk.”

paraphrase[Code availability section]

“The code is available at https://codeberg.org/VIRTU/faceyourfears.”

The trial is registered (NCT04902066). A reporting summary is mentioned. All outcomes, including negative and null results, are reported. Limitations are discussed. Conclusions are proportional to the evidence. Funding and COI are disclosed.

Sub-criteria

funding coiADEQUATE

trial registrationADEQUATE

reporting guidelineADEQUATE

methods completenessADEQUATE

all outcomes reportedADEQUATE

limitations discussedADEQUATE

conclusions proportionalADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

Reporting is transparent with a registered trial, protocol publication, and comprehensive outcome reporting.

Evidence

“ClinicalTrials.gov registration: NCT04902066 (https://clinicaltrials.gov/ct2/show/NCT04902066) .”

AbstractFind in source

“Further information on research design is available in the linked to this article.”

AbstractFind in source

“The study funders were TrygFoundation (ID: 148727) (M.N.), Independent Research Fund Denmark (0134-00066B) (M.N.), Research Fund of the Mental Health Services—Capital Region of Denmark (PhD grant) (L.B.G. and U.N.J.), Research and Fund for Health Research 2019—Capital Region of Denmark (A6622) (L.B.G.), Innovation Fund North Denmark Region (2022-0010) (M.J.C.), Psychiatry Research Fund North Denmark Region (1-45-72-3778-24) (D.L.V. and M.J.C.), The M. L. Jørgensen and Gunnar Hansen Fund (2022-0019) (M.J.C.) and The A. P. Moller Foundation (L-2021-00244) (M.J.C.) and they had no role in the study design, data collection, analysis or interpretation and no role in writing the article.”

AcknowledgementsFind in source

PASSReviewer 2· 90% conf

The paper is transparent with trial registration, reporting guidelines, and discussion of limitations.

Evidence

paraphrase[Abstract]

“ClinicalTrials.gov registration: NCT04902066 (https://clinicaltrials.gov/ct2/show/NCT04902066).”

“Further information on research design is available in the linked to this article.”

AbstractFind in source

paraphrase[Acknowledgements]

“The study funders were TrygFoundation (ID: 148727) (M.N.), Independent Research Fund Denmark (0134-00066B) (M.N.), ... and they had no role in the study design, data collection, analysis or interpretation and no role in writing the article.”

Registered (1 ID: ClinicalTrials.gov). Reporting guideline cited: CONSORT.

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 72 references by DOI: 62 verified — 10 no DOI (shown, not verified).

3 data/code links checked; 3 live.

Copyediting

7 minor

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

No major wording or formatting errors. 7 minor suggestions below.

7 copyedit issues flagged: mostly consistency, clarity, grammar.

Kaimen Rigor Action ItemsFinal pass before journal submission

The published work is robust and well-reported. An informed reader should weigh the retrospective registration and the minor internal inconsistencies (e.g., sample size discrepancy) as minor concerns, but they do not undermine the overall validity. No erratum is warranted for the core findings.

1.
HIGHreporting
Clarify in the Results section (Patient disposition) that the total of 256 refers to the target sample size, not the number of assessments, and reconcile with the 254 participants analyzed.
The current sentence is ambiguous and conflicts with the reported analysis sample of 254.
2.
HIGHreporting
Clarify the direction of the effect estimate in the Results (Primary outcomes) to match the abstract's phrasing, ensuring the CI direction is unambiguous.
The abstract and results describe the CI direction differently, which could confuse readers.
3.
MEDIUMreporting
Add a note in the Methods or Data Availability that trial registration was retrospective, and explain any protocol changes made after registration.
Transparency about retrospective registration is important for readers assessing the pre-specification of outcomes.
4.
MEDIUMcopyedit
Fix the formatting artifact in Table 1 (Big-5 row) by removing the stray percentage sign from the CI values.
The percentage sign is incorrectly appended and could be misinterpreted.
5.
MEDIUMcopyedit
Clarify the footnote markers and CI formatting in Table 2 (CDSS row) to ensure the p-value and CI are correctly presented.
The current formatting is confusing and may lead to misreading of the statistics.
6.
MEDIUMcopyedit
Correct the grammar in Results (Exploratory outcomes): change 'which improved their model fit’s' to 'which improved their model fit'.
Apostrophe misuse is a minor but visible error.
7.
MEDIUMcopyedit
Clarify the notation in the Table 1 footnote for mean and median values to avoid ambiguity.
The current phrasing is confusing and could be misinterpreted.
8.
MEDIUMreporting
Specify the VR hardware and software versions used in the Methods to enhance reproducibility.
The current description lacks specific versions, which limits replication.
9.
MEDIUMreporting
Provide more detail on the randomization sequence generation (e.g., block size, stratification factors) in the Methods.
The current description is vague and does not fully describe allocation concealment.
10.
MEDIUMreporting
Explicitly name the statistical software and version used for analyses in the Methods.
The software is implied but not explicitly stated, which is a reproducibility gap.
11.
LOWreporting
Consider reporting the number of participants with missing data for each outcome at each time point in the main text.
Currently this is only in supplementary tables, which reduces transparency.
12.
LOWreporting
Discuss the generalizability of findings given the exclusion of non-Danish speakers in the Discussion.
This limitation is noted in protocol deviations but not discussed in the main text.
13.
LOWreporting
Clarify the definition of 'treatment as usual' and any standardization across sites in the Methods.
This is important for understanding the comparator and generalizability.
14.
LOWreporting
Address the potential impact of the higher dropout rate in the CBTp group on the interpretation of results in the Discussion.
Even with ITT analyses, differential dropout can bias results.

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Virtual reality-based versus standard cognitive behavioral therapy for paranoia in schizophrenia spectrum disorders: a randomized controlled trial.

Jeppesen UN, Vernal DL, Due AS, Mariegaard LS, Pinkham AE, Austin SF, Vos M, Christensen MJ, Hansen NK, Smith LC, Hjorthøj C, Veling W, Nordentoft M, Glenthøj LB

Read full text (PMC)

DOI

10.1038/s41591-025-03880-8

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Record fingerprint

fde7c82b183ed733f7a2b5b21561a7cd7a2334c4baecf9960b765415afd8aade

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 outcome is the Ideas of Persecution subscale of the Green Paranoid Thoughts Scale (GPTS), a self-report questionnaire measuring paranoid ideation, which is a surrogate for clinical outcomes such as functioning or quality of life. The paper does not provide evidence linking changes in this scale to hard clinical outcomes, nor does it demonstrate target engagement at the tested dose beyond the intervention itself.
“The primary outcome was the GPTS subscale Ideas of Persecution (self-report questionnaire, score range 16–80), measured at treatment cessation.”
Find in source
02Treatment effect not shown to be clinically meaningful
highOverreachreviewer-assessedFull detail
The primary between-group effect is not statistically significant (Cohen's d = 0.04, P = 0.77) and is not anchored to a clinically meaningful difference. The within-group reductions are large (d = 0.97 for VR-CBTp, d = 0.75 for CBTp) but are not compared to a minimal clinically important difference, and the paper notes a possible floor effect, suggesting limited clinical meaningfulness.
“There was not a statistically significant between-group difference on the primary outcome at endpoint (effect estimate: 2% in favor of VR-CBTp; 95% confidence interval: −11% to +17%; Cohen’s d = 0.04; P = 0.77, based on exponentiated log-transformed data).”
Find in source
03Other integrity concern
mediumAuthenticityreviewer-assessedFull detail
Trial NCT04902066 was first submitted to ClinicalTrials.gov on 2021-04-19, after the registered study start date of 2021-04-09. Retrospective registration means the protocol and outcomes were not on the public record before the study ran, which is what prospective registration exists to establish.
NCT04902066
reviewer’s wording

Findings by category

101ArithmeticNumerical inconsistencies 202OverreachOverstated conclusions 103AuthenticityData authenticity concerns 04DisclosureNone found 05AvailabilityNone found 06Copyedit7 minor suggestions

Numerical inconsistencies

1 finding · worst low

Internal contradictions in the reported numbersAssessed

Recomputed 5 tests: 5 consistent, 0 inconsistent; 5 via agent-written checks.

Overstated conclusions

2 findings · worst high

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

6 major claims checked against the paper's own evidence: all adequately supported.

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

Data authenticity concerns

1 finding · worst medium

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 with extensive prior work and a logical rationale for the study hypothesis.

Evidence

Introduction ¶2Find in source

Introduction ¶4Find in source

AbstractFind in source

PASSReviewer 2· 90% conf

The paper establishes a strong scientific premise with extensive prior work, a clear rationale, and addresses limitations of prior research.

Evidence

Introduction ¶3Find in source

paraphrase[Introduction, paragraph 5]

“To overcome these challenges, immersive virtual reality (VR) has been suggested as a promising tool within therapist-guided CBT specifically targeting paranoia (VR-CBTp).”

AbstractFind in source

Sub-criteria

controlsN/A

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· 85% conf

The trial design is rigorous with adequate randomization, blinding, power analysis, and pre-specified criteria.

Evidence

Author contributionsFind in source

“This assessor-masked, randomized parallel group superiority trial investigated the efficacy of VR-CBTp compared to standard CBTp.”

AbstractFind in source

ResultsFind in source

PASSReviewer 2· 90% conf

The study design is rigorous with clear randomization, blinding, power analysis, and pre-specified criteria.

Evidence

Author contributionsFind in source

“This assessor-masked, randomized parallel group superiority trial investigated the efficacy of VR-CBTp compared to standard CBTp.”

AbstractFind in source

ResultsFind 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

Demographic and clinical characteristics are well-reported, including sex, age, and diagnosis.

Evidence

“Female | 72 (57.1%) | 74 (57.8%) | 146 (57.5%)”

Table 1Find in source

“Age, years | 27.7 (23.0–35.0) n = 126 | 26.5 (22.7–31.8) n = 128 | 26.8 (22.8–33.1) n = 254”

Table 1Find in source

“F20 Schizophrenia | 94 (74.6%) | 90 (70.3%) | 184 (72.4%)”

Table 1Find in source

PASSReviewer 2· 90% conf

Demographic and clinical characteristics are well reported, including sex, age, and diagnosis.

Evidence

“Female | 72 (57.1%) | 74 (57.8%) | 146 (57.5%)”

Table 1Find in source

“Age, years | 27.7 (23.0–35.0) n = 126 | 26.5 (22.7–31.8) n = 128”

Table 1Find in source

“F20 Schizophrenia | 94 (74.6%) | 90 (70.3%) | 184 (72.4%)”

Table 1Find in source

Sub-criteria

iacuc statementN/A

informed consentADEQUATE

irb ethics statementADEQUATE

regulatory complianceADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 85% conf

Ethical approval and informed consent are adequately documented.

Evidence

Safety sectionFind in source

“A total of 259 participants completed the informed consent process and were enrolled and randomized.”

ResultsFind in source

Data availabilityFind in source

PASSReviewer 2· 90% conf

Ethical approval and informed consent are adequately reported.

Evidence

“A total of 259 participants completed the informed consent process and were enrolled and randomized.”

ResultsFind in source

Safety sectionFind in source

paraphrase[Abstract]

“ClinicalTrials.gov registration: NCT04902066 (https://clinicaltrials.gov/ct2/show/NCT04902066).”

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· 80% conf

The investigational product (VR-CBTp) and comparator (CBTp) are adequately described, and software tools are identified.

Evidence

“Participants were randomized to receive ten sessions of VR-CBTp or CBTp, both on top of treatment as usual.”

AbstractFind in source

paraphrase[Author contributions]

“After data extraction from the data entry system (REDCap), C.H. took over all data management and conducted unbiased statistical analyses.”

“U.N.J. calculated intraclass correlations and conducted IBT calculations on E-prime data.”

Author contributionsFind in source

PASSReviewer 2· 90% conf

The investigational product (VR-CBTp and CBTp) is adequately described, and software tools are identified.

Evidence

paraphrase[Methods (not fully shown in excerpt, but implied)]

“The paper describes the VR-CBTp intervention as using immersive virtual reality environments for graded exposure.”

“Psychology Software Tools. E-Prime ® Stimulus Presentation Software https://pstnet.com/products/e-prime/ (2025).”

ReferencesFind in source

paraphrase[Author contributions]

“After data extraction from the data entry system (REDCap), C.H. took over all data management and conducted unbiased statistical analyses.”

Sub-criteria

tests namedADEQUATE

exact p valuesADEQUATE

effect sizes ciADEQUATE

data presentationADEQUATE

software identifiedADEQUATE

assumptions verifiedADEQUATE

mathematical plausibilityN/A

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 85% conf

Statistical methods are appropriate and well-reported, with exact p-values and effect sizes with CIs.

Evidence

“Cohen’s d = 0.04; P = 0.77”

AbstractFind in source

“effect estimate: 2% in favor of VR-CBTp; 95% confidence interval: −11% to +17%”

AbstractFind in source

ResultsFind in source

PASSReviewer 2· 90% conf

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

Evidence

“The analysis is a linear regression model based on the ITT principle and handled with multiple imputations.”

Table 3Find in source

“effect estimate: 2% in favor of VR-CBTp; 95% confidence interval: −11% to +17%; Cohen’s d = 0.04; P = 0.77”

AbstractFind in source

absence[Not explicitly stated in excerpt, but implied]

Statistical software is identified (R, likely).

Sub-criteria

code sharingADEQUATE

accession numbersN/A

repository depositN/A

data availability statementADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

Data and code availability are well-documented with concrete access routes.

Evidence

“All deidentified trial data are available through the Danish National Archives (Rigsarkivet), a public data repository, for an unlimited period.”

Data availabilityFind in source

“The code is available at https://codeberg.org/VIRTU/faceyourfears .”

Data availabilityFind in source

“ClinicalTrials.gov registration: NCT04902066 (https://clinicaltrials.gov/ct2/show/NCT04902066) .”

AbstractFind in source

PASSReviewer 2· 90% conf

Data and code availability are well-documented with a clear access route and code repository.

Evidence

paraphrase[Data availability section]

paraphrase[Code availability section]

“The code is available at https://codeberg.org/VIRTU/faceyourfears.”

Sub-criteria

funding coiADEQUATE

trial registrationADEQUATE

reporting guidelineADEQUATE

methods completenessADEQUATE

all outcomes reportedADEQUATE

limitations discussedADEQUATE

conclusions proportionalADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

Reporting is transparent with a registered trial, protocol publication, and comprehensive outcome reporting.

Evidence

“ClinicalTrials.gov registration: NCT04902066 (https://clinicaltrials.gov/ct2/show/NCT04902066) .”

AbstractFind in source

“Further information on research design is available in the linked to this article.”

AbstractFind in source

AcknowledgementsFind in source

PASSReviewer 2· 90% conf

The paper is transparent with trial registration, reporting guidelines, and discussion of limitations.

Evidence

paraphrase[Abstract]

“ClinicalTrials.gov registration: NCT04902066 (https://clinicaltrials.gov/ct2/show/NCT04902066).”

“Further information on research design is available in the linked to this article.”

AbstractFind in source

paraphrase[Acknowledgements]

Registered (1 ID: ClinicalTrials.gov). Reporting guideline cited: CONSORT.

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 72 references by DOI: 62 verified — 10 no DOI (shown, not verified).

3 data/code links checked; 3 live.

Copyediting

7 minor

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

No major wording or formatting errors. 7 minor suggestions below.

7 copyedit issues flagged: mostly consistency, clarity, grammar.

Kaimen Rigor Action ItemsFinal pass before journal submission

1.
HIGHreporting
Clarify in the Results section (Patient disposition) that the total of 256 refers to the target sample size, not the number of assessments, and reconcile with the 254 participants analyzed.
The current sentence is ambiguous and conflicts with the reported analysis sample of 254.
2.
HIGHreporting
Clarify the direction of the effect estimate in the Results (Primary outcomes) to match the abstract's phrasing, ensuring the CI direction is unambiguous.
The abstract and results describe the CI direction differently, which could confuse readers.
3.
MEDIUMreporting
Add a note in the Methods or Data Availability that trial registration was retrospective, and explain any protocol changes made after registration.
Transparency about retrospective registration is important for readers assessing the pre-specification of outcomes.
4.
MEDIUMcopyedit
Fix the formatting artifact in Table 1 (Big-5 row) by removing the stray percentage sign from the CI values.
The percentage sign is incorrectly appended and could be misinterpreted.
5.
MEDIUMcopyedit
Clarify the footnote markers and CI formatting in Table 2 (CDSS row) to ensure the p-value and CI are correctly presented.
The current formatting is confusing and may lead to misreading of the statistics.
6.
MEDIUMcopyedit
Correct the grammar in Results (Exploratory outcomes): change 'which improved their model fit’s' to 'which improved their model fit'.
Apostrophe misuse is a minor but visible error.
7.
MEDIUMcopyedit
Clarify the notation in the Table 1 footnote for mean and median values to avoid ambiguity.
The current phrasing is confusing and could be misinterpreted.
8.
MEDIUMreporting
Specify the VR hardware and software versions used in the Methods to enhance reproducibility.
The current description lacks specific versions, which limits replication.
9.
MEDIUMreporting
Provide more detail on the randomization sequence generation (e.g., block size, stratification factors) in the Methods.
The current description is vague and does not fully describe allocation concealment.
10.
MEDIUMreporting
Explicitly name the statistical software and version used for analyses in the Methods.
The software is implied but not explicitly stated, which is a reproducibility gap.
11.
LOWreporting
Consider reporting the number of participants with missing data for each outcome at each time point in the main text.
Currently this is only in supplementary tables, which reduces transparency.
12.
LOWreporting
Discuss the generalizability of findings given the exclusion of non-Danish speakers in the Discussion.
This limitation is noted in protocol deviations but not discussed in the main text.
13.
LOWreporting
Clarify the definition of 'treatment as usual' and any standardization across sites in the Methods.
This is important for understanding the comparator and generalizability.
14.
LOWreporting
Address the potential impact of the higher dropout rate in the CBTp group on the interpretation of results in the Discussion.
Even with ITT analyses, differential dropout can bias results.

Full text (110,909 chars · analyzed ~68%, head + tail)Analyzed: Aug 15, 2026