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Cited by 1,017Meta-analysis and systematic reviewsStatistical Methods in EpidemiologyDelphi Technique in Research

The DOI matches its Crossref record; 31 of the 32 references it cites were found in a registry or an index.

Systematic Review: Why sources of heterogeneity in meta-analysis should be investigated

Open access
Thompson, S G·1994·BMJ
DOI 10.1136/bmj.309.6965.1351PMC PMC2541868
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Abstract

Although meta-analysis is now well established as a method of reviewing evidence, an uncritical use of the technique can be very misleading. One common problem is the failure to investigate appropriately the sources of heterogeneity, in particular the clinical differences between the studies included. This paper distinguishes between the concepts of clinical and statistical heterogeneity and exemplifies the importance of investigating heterogeneity by using published meta-analyses of epidemiological studies of serum cholesterol concentration and clinical trials of its reduction. Although not without some dangers of speculative conclusions, prompted by overzealous inspection of the data to hand, a sensible investigation of sources of heterogeneity should increase both the scientific and the clinical relevance of the results of meta-analyses.

Overview

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Crossref · 10.1136/bmj.309.6965.1351

Cites

31 of 31 references verified0 citation errors · 0 not checkable

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Citations

Cites

Research works printed but not linked: 4

  1. Oxman A .Preparing and maintaining systematic reviews. In: Sackett D , ed Cochrane Collaboration Handbook.Section VI. Oxford:Cochrane Collaboration,1994.
  2. Meier, 1987, Meta-analysis of clinical trials as a scientific discipline [commentary]., Statist Med, 6, 329, 10.1002/sim.4780060322 · DOI
  3. 10.1136/bmj.308.6921.81 · DOI
  4. Schulz KF Chalmers I Hayes RJ Altman DG .Empirical evidence of bias: dimensions of methodologic quality are associated with estimates of treatment effects in 250 controlled trials from 33 meta-analyses. JAMA (in press).

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Metadata

Authors
Thompson, S. G.
Affiliations
London School of Hygiene & Tropical Medicine (GB)
Corresponding author
Thompson, S G
ORCID
Thompson, S G
Venue
BMJ
Publisher
BMJ
Published
1994-11-19
Volume
309
Issue
6965
Pages
1351-1355
ISSN
  • 0007-1447 (ISSN-L)
  • 0959-8138
  • 1468-5833
DOI
10.1136/bmj.309.6965.1351
PMC
PMC2541868
OpenAlex
W1511524925
Cited by
1,017
References
32
Citations by year
2026: 23 · 2025: 35 · 2024: 38 · 2023: 29 · 2022: 30 · 2021: 47 · 2020: 38 · 2019: 32 · 2018: 36 · 2017: 26 · 2016: 24 · 2015: 24 · 2014: 31 · 2013: 48 · 2012: 51
FWCI
3.70
Type
journal article
Language
en
Open access
Licence
www.bmj.com/company/legal-information/terms-conditions/legal-information/tdm-licencepolicy (tdm)
Locations
  • BMJ (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
  • Social Sciences › Sociology and Political Science › Delphi Technique in Research
Keywords
meta-analysis heterogeneity, clinical heterogeneity, statistical heterogeneity, serum cholesterol, cholesterol lowering, meta-analysis methodology, overfitting
MeSH terms
Adult, Aged, Aging, Cholesterol, Clinical Trials as Topic, Humans, Middle Aged, Neoplasms, Research Design, Meta-Analysis as Topic, Randomized Controlled Trials as Topic, Risk Assessment

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