Clinical effectiveness of an online supervised group physical and mental health rehabilitation programme for adults with post-covid-19 condition (REGAIN study): multicentre randomised controlled trial.

Name: Αlpha¹ Rigor Record — Clinical effectiveness of an online supervised group physical and mental health rehabilitation programme for adults with post-covid-19 condition (REGAIN study): multicentre randomised controlled trial.
Item: Clinical effectiveness of an online supervised group physical and mental health rehabilitation programme for adults with post-covid-19 condition (REGAIN study): multicentre randomised controlled trial.
Rating: 59
Author: Αlpha¹

McGregor G, Sandhu H, Bruce J, Sheehan B, McWilliams D, Yeung J, Jones C, Lara B, Alleyne S, Smith J, Lall R, Ji C, Ratna M, Ennis S, Heine P, Patel S, Abraham C, Mason J, Nwankwo H, Nichols V, Seers K, Underwood M

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Αlpha¹ Rigor Review — 2★ (Weak), 0 critical, 2 high issues for “Clinical effectiveness of an online supervised group physical and mental health rehabilitation programme for adults with post-covid-19 condition (REGAIN study): multicentre randomised controlled trial.”

Links back to this Rigor Record.

Αlpha¹ Editorial

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

Αlpha¹ Rigor Review

Rigor Reviewed

2 / 5

Weak — serious problems found

Interventional Study

Critical

High-priority

How this rating was calculated▸

Started at 5★ — deductions

IntegrityIntegrity concern ×2−1★
StatisticsStatistic did not reproduce−0.5★
ClaimsEfficacy rests on an unvalidated surrogate endpoint−0.5★
ClaimsTreatment effect not shown to be clinically meaningful−0.5★
StatisticsPrinted percentage does not match its own count (capped) ×12−0.25★
ReportingData & code availability partially met−0.25★

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

Not verified in this report

The numeric-impossibility checks (GRIM/GRIMMER/DEBIT/SPRITE) did not run: 32 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.
No data or code availability links were detected to verify.

Problems surfaced7 types

Numerical inconsistencies3

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.

Summary statistic impossible for the stated N (GRIM/GRIMMER)Recomputed
Printed percentage does not match its own countRecomputed
Internal contradictions in the reported numbersAssessed

Overstated conclusions3

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

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 pragmatic RCT of an online rehabilitation programme for post-covid-19 condition. The main methodological strength is the rigorous design with adequate randomization, blinding of outcome assessment, and pre-specified analyses. The primary weakness is the vague data availability statement and lack of code sharing, which limits reproducibility.

Both reviewers independently scored all eight dimensions and agreed on every status; no divergence required reconciliation. The statistics verification component covered only a subset of reported tests (those with test statistics/df or effect estimates with CIs); 13 of 17 tests were not machine-verifiable, so the absence of detected errors does not confirm overall statistical correctness. The citation check found no retracted or unresolved references.

5 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.

Recomputed 3 tests: 3 consistent, 0 inconsistent; 1 recomputed directly from the reported test statistics, 2 via agent-written checks. 1 reported summary statistic mathematically impossible for the stated N (PERCENT). 12 printed percentages that do not match their own count.

2 integrity concerns flagged (0 high).

Reporting

Eight Dimensions7 pass · 1 warn

The introduction cites epidemiological data on long covid prevalence and symptoms, and notes that only small quasi-experimental studies have investigated exercise-based rehabilitation, with no high-quality definitive evidence. The rationale for a multicomponent physical and mental health rehabilitation programme is logically linked to the biopsychosocial model and evidence from other long-term conditions. The paper does not explicitly discuss limitations of prior research in detail, but the gap in evidence is clearly stated.

Sub-criteria

prior work citedADEQUATE

premise rationaleADEQUATE

limitations addressedINADEQUATE

Per reviewer (2) — the votes behind the verdict

PASSReviewer 1· 90% conf

The paper establishes a clear scientific premise, citing prior research and providing a logical rationale for the study.

Evidence

direct quote[Introduction, paragraph 1]

“Across the World Health Organization European Region during the first two years of the covid-19 pandemic, more than 17 million people may have experienced covid-19 symptoms lasting more than four weeks.”