Cited by 149Meta-analysis and systematic reviewsStatistical Methods in Clinical TrialsPharmaceutical industry and healthcare

The DOI matches its Crossref record; 40 of the 46 references it cites were found in a registry or an index; none of the 34 sources its claims cite is checked for support yet.

Evaluation of Evidence of Statistical Support and Corroboration of Subgroup Claims in Randomized Clinical Trials

Open access

Abstract

Importance: Many published randomized clinical trials (RCTs) make claims for subgroup differences. Objective: To evaluate how often subgroup claims reported in the abstracts of RCTs are actually supported by statistical evidence (P < .05 from an interaction test) and corroborated by subsequent RCTs and meta-analyses. Data Sources: This meta-epidemiological survey examines data sets of trials with at least 1 subgroup claim, including Subgroup Analysis of Trials Is Rarely Easy (SATIRE) articles and Discontinuation of Randomized Trials (DISCO) articles. We used Scopus (updated July 2016) to search for English-language articles citing each of the eligible index articles with at least 1 subgroup finding in the abstract. Study Selection: Articles with a subgroup claim in the abstract with or without evidence of statistical heterogeneity (P < .05 from an interaction test) in the text and articles attempting to corroborate the subgroup findings. Data Extraction and Synthesis: Study characteristics of trials with at least 1 subgroup claim in the abstract were recorded. Two reviewers extracted the data necessary to calculate subgroup-level effect sizes, standard errors, and the P values for interaction. For individual RCTs and meta-analyses that attempted to corroborate the subgroup findings from the index articles, trial characteristics were extracted. Cochran Q test was used to reevaluate heterogeneity with the data from all available trials. Main Outcomes and Measures: The number of subgroup claims in the abstracts of RCTs, the number of subgroup claims in the abstracts of RCTs with statistical support (subgroup findings), and the number of subgroup findings corroborated by subsequent RCTs and meta-analyses. Results: Sixty-four eligible RCTs made a total of 117 subgroup claims in their abstracts. Of these 117 claims, only 46 (39.3%) in 33 articles had evidence of statistically significant heterogeneity from a test for interaction. In addition, out of these 46 subgroup findings, only 16 (34.8%) ensured balance between randomization groups within the subgroups (eg, through stratified randomization), 13 (28.3%) entailed a prespecified subgroup analysis, and 1 (2.2%) was adjusted for multiple testing. Only 5 (10.9%) of the 46 subgroup findings had at least 1 subsequent pure corroboration attempt by a meta-analysis or an RCT. In all 5 cases, the corroboration attempts found no evidence of a statistically significant subgroup effect. In addition, all effect sizes from meta-analyses were attenuated toward the null. Conclusions and Relevance: A minority of subgroup claims made in the abstracts of RCTs are supported by their own data (ie, a significant interaction effect). For those that have statistical support (P < .05 from an interaction test), most fail to meet other best practices for subgroup tests, including prespecification, stratified randomization, and adjustment for multiple testing. Attempts to corroborate statistically significant subgroup differences are rare; when done, the initially observed subgroup differences are not reproduced.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

This meta-epidemiological survey examined subgroup claims in randomized trial abstracts and found that only a minority were backed by a significant interaction test. Subsequent attempts to corroborate those supported findings were rare and did not reproduce the original subgroup differences.

Key findings

  • Among 169 trials with subgroup claims anywhere in the text, 64 (37.9%) made at least one claim in the abstract, yielding 117 abstract-level subgroup claims.
  • Only 46 of 117 claims (39.3%) had statistical support from a significant interaction test; among these 46 findings, 16 (34.8%) used a randomization stratification variable, 13 (28.3%) were prespecified, and 1 (2.2%) adjusted for multiple testing.
  • Just 5 of the 46 supported findings (10.9%) had at least one pure corroboration attempt by a later trial or meta-analysis; none of these attempts found a significant subgroup interaction, and available effect estimates moved toward the null.
  • Modified corroboration attempts were identified for 4 findings in 3 index articles, often using different subgroup definitions or measurements.

Methods

  • Design: meta-epidemiological survey using trials with subgroup claims from the SATIRE and DISCO study groups; 169 index articles were screened, and 64 with abstract subgroup claims were included.
  • Data sources: Scopus searches updated July 2016 for English-language articles citing eligible index articles; two reviewers extracted data, with three additional reviewers arbitrating discrepancies.
  • Analysis: subgroup-level effect sizes and standard errors were calculated where possible, interaction P values were assessed, and heterogeneity was re-evaluated with Cochran Q tests using R, metafor, RevMan, and DerSimonian-Laird random-effects models; P values were two-tailed.

Limitations

  • Paper-stated: the follow-up window may have been too short, since SATIRE articles appeared in 2007 and DISCO articles with subgroup findings appeared between 2002 and 2012, and 3 to 4 years may not allow a new trial to publish a corroboration attempt.
  • Paper-stated: the authors relied on reported data and the effect measures chosen by original authors, and interaction tests can be sensitive to the effect measure used, which may have affected classification of some findings.
  • Paper-stated: the Scopus search may have missed corroboration attempts, particularly trials that did not cite the original articles making similar subgroup claims.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1001/jamainternmed.2016.9125

Cites

40 of 40 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

0 of 34 cited sources checked · 0 supported · 0 flagged

Show all 35 claims

  • Probably not a substantial claim. 9
  • It may state two separate claims as one. 8
  • The quote only partly states this claim. 1
17 of 17
  • The authors state this as an assumption.

    Authors are more careful and selective about reporting subgroup differences in abstracts.

    “Presumably, authors are more careful and selective about reporting subgroup differences in abstracts because these claims are most visible to the research community.”
  • The authors state this as an assumption.

    No previous studies have evaluated the credibility of subgroup findings by checking whether they are corroborated.

    “Furthermore, to our knowledge, no previous studies have attempted to evaluate the credibility of subgroup findings by checking to see if they are corroborated (eg, new studies producing the same results with the same experimental methods).”
  • The authors state this as an assumption.

    The Scopus search strategy captured most corroboration attempts that could have occurred after the index articles' publication.

    “We believe that our search strategy was able to capture most corroboration attempts that could have occurred after the publication date of the index articles.”
  • The paper relies on this without support.

    Interaction tests are sensitive to subgroup definitions, the effect estimates used, and the exact measurements used for subgroup or outcome variables.

    “Interaction tests are sensitive to subgroup definitions (ie, 3 group levels or 2 group levels), the effect estimates used (ie, risk ratios or odds ratios), and the exact measurements used for the subgroup or outcome variables.”
  • The paper relies on this without support.

    Subgroup differences reported in abstracts are the most visible ones.

    “We focused on subgroup differences that appeared in the abstract of an article, which are the most visible ones.”
5 of 5

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

  • Incorrect percentage for significant reported interaction tests

    Minor

    The discussion reports 24 of 33 as 69.7%, but that fraction is 72.7%, as stated earlier in the results.

    Reported 69.7 · recomputed 72.727273

1 of 1

Citations

Cites

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Items 101–149 of 149

Metadata

Authors
Wallach, J. D., Sullivan, P. G., Trepanowski, J. F., Sainani, K. L., Steyerberg, E. W., & Ioannidis, J. P. A.
Affiliations
  • Stanford Medicine (US)
  • Erasmus MC (NL)
Corresponding author
Ioannidis, John P. A.
Venue
JAMA Internal Medicine
Published
2017-04-01
Volume
177
Issue
4
Pages
554
ISSN
2168-6106 (ISSN-L)
OpenAlex
W2595252694
Cited by
148
References
46
Citations by year
2026: 9 · 2025: 17 · 2024: 13 · 2023: 9 · 2022: 14 · 2021: 13 · 2020: 21 · 2019: 20 · 2018: 18 · 2017: 14
FWCI
17.86
Type
journal article
Language
en
Open access
Locations
  • JAMA Internal Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • PubMed Central (acceptedVersion)
  • EUR Research Repository (Erasmus University Rotterdam) (submittedVersion)
Funders
  • National Institutes of Health (UL1TR001085)
  • National Heart, Lung, and Blood Institute (T32HL007034)
  • National Institute of Neurological Disorders and Stroke (U01NS086294)
  • National Center for Advancing Translational Sciences
Topics
  • Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
  • Health Sciences › Nursing › Issues, ethics and legal aspects › Pharmaceutical industry and healthcare
Keywords
subgroup analysis, interaction testing, statistical heterogeneity, meta-epidemiology, randomized controlled trials, stratified randomization, multiple testing correction, publication bias, meta-analysis, trial discontinuation, satire, disco
MeSH terms
Data Interpretation, Statistical, Diagnosis-Related Groups, Humans, Publishing, Randomized Controlled Trials as Topic, Evidence-Based Medicine, Intention to Treat Analysis

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

A language model drew the claims from the paper on 2026-10-06, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-10-06 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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