Evidence map›Paper›PMID 42549287›Full record

ArticleCochrane evidence synthesis and methods2026

Introduction to Trial-Level Subgroup Analysis: A Tutorial.

Peter J Godolphin, Conor D Tweed, David J Fisher

Abstract read
In one paragraph

Article in Cochrane evidence synthesis and methods, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Peter J GodolphinUCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology University College London London UK.ORCID https://orcid.org/0000-0003-0648-0992
Conor D TweedUCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology University College London London UK.ORCID https://orcid.org/0000-0001-6021-8237
David J FisherUCL Innovative Clinical Trials Unit, Institute of Clinical Trials and Methodology University College London London UK.ORCID https://orcid.org/0000-0002-2512-2296

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

This tutorial introduces the concept of trial-level subgroup analysis in meta-analysis. We describe the rationale for conducting subgroup analyses, distinguish trial-level from participant-level characteristics, outline how to properly interpret effects within subgroups, and illustrate how to perform a trial-level subgroup analysis, including formal statistical testing for differences between subgroups. A complementary micro-learning module is provided to support additional learning of these concepts.

Identifiers

PMID42549287
PMCPMC13431748

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.