Lateral episiotomy or no episiotomy in vacuum assisted delivery in nulliparous women (EVA): multicentre, open label, randomised controlled trial.

Name: Αlpha¹ Rigor Record — Lateral episiotomy or no episiotomy in vacuum assisted delivery in nulliparous women (EVA): multicentre, open label, randomised controlled trial.
Item: Lateral episiotomy or no episiotomy in vacuum assisted delivery in nulliparous women (EVA): multicentre, open label, randomised controlled trial.
Rating: 96
Author: Αlpha¹

Bergendahl S, Jonsson M, Hesselman S, Ankarcrona V, Leijonhufvud Å, Wihlbäck AC, Wallström T, Rydström E, Friberg H, Kopp Kallner H, Brismar Wendel S

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Αlpha¹ Rigor Review — 3.75★ (Adequate), 0 critical, 2 high issues for “Lateral episiotomy or no episiotomy in vacuum assisted delivery in nulliparous women (EVA): multicentre, open label, randomised controlled trial.”

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Αlpha¹ Editorial

This rigor review was examined and confirmed by Αlpha¹ Editorial · August 16, 2026

Αlpha¹ Rigor Review

Rigor Reviewed

3.75 / 5

Adequate — real issues to address

Interventional Study

Critical

High-priority

How this rating was calculated▸

Started at 5★ — deductions

IntegrityIntegrity concern−0.5★
ClaimsEfficacy rests on an unvalidated surrogate endpoint−0.5★
ReportingData & code availability partially met−0.25★

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

Not verified in this report

No data or code availability links were detected to verify.

Problems surfaced3 types

Numerical inconsistencies1

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

Overstated conclusions1

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

Reporting gaps1

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.

Data/code availability incompleteAssessed

This Αlpha¹ Rigor Review uses AI 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 randomised controlled trial with a clear scientific premise, rigorous design, and appropriate statistical analysis. The main weakness is the vague data availability statement, which lacks a concrete access mechanism for the data. Minor copyedit issues (e.g., a typo in a BMI range and an incomplete sentence) do not affect the scientific integrity.

Both reviewers independently scored all eight dimensions and agreed on every status; no divergence required reconciliation. The study is an interventional RCT; animal-related and cell-line criteria were not applicable. The statistics verification recomputed only 1 test (the primary chi-square) and found it consistent; other reported statistics were not machine-verified and should not be assumed correct. Citation check found no retracted or unresolved references.

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

Premise concern: surrogate not validated for clinical benefit.

Recomputed 1 test: 1 consistent, 0 inconsistent; 1 via agent-written checks.

1 integrity concern flagged (0 high).

Reporting

Eight Dimensions7 pass · 1 warn

The introduction cites a Cochrane review, a 2022 meta-analysis, and observational studies, acknowledging conflicting results and the lack of adequately sized RCTs. The rationale links the uncertainty to the need for a trial, and the hypothesis follows logically. Limitations of prior observational studies (lack of standardisation, confounding) are explicitly discussed.

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 prior work cited, a logical rationale, and addresses limitations of prior research.

Evidence

direct quote[Introduction, paragraph 1]

“A Cochrane review of randomised controlled trials has concluded that routine episiotomy may increase the risk of obstetric anal sphincter injury in non-instrumental birth, while lateral or mediolateral episiotomy might prevent obstetric anal sphincter injury in vacuum extraction in nulliparous women, based on results from pooled observational studies.”