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Cited by 307Meta-analysis and systematic reviewsStatistical Methods in Clinical TrialsPharmaceutical industry and healthcare

The DOI matches its Crossref record; 72 of the 72 references it cites were found in a registry or an index.

Single-Center Trials Show Larger Treatment Effects Than Multicenter Trials: Evidence From a Meta-epidemiologic Study

Dechartres, Agnes, Boutron, Isabelle, Trinquart, Ludovic, Charles, Pierre, Ravaud, Philippe·2011·Annals of Internal Medicine
DOI 10.7326/0003-4819-155-1-201107050-00006
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Abstract

BACKGROUND: A recent study suggested that results of single-center trials are frequently contradicted when similar trials are performed in multicenter settings. PURPOSE: To perform a meta-epidemiologic study to evaluate whether estimates of treatment effect differ between single-center and multicenter randomized, controlled trials (RCTs). DATA SOURCES: MEDLINE was searched via PubMed for meta-analyses of RCTs with binary outcomes that were published between August 2008 and January 2009 and in the first 6 months of 2010 in the 10 leading journals of each medical specialty. One issue of the Cochrane Database of Systematic Reviews was also searched. STUDY SELECTION: All individual RCTs included in the meta-analyses were selected. DATA EXTRACTION: Data were extracted and their quality was assessed by use of the risk of bias tool of the Cochrane Collaboration. DATA SYNTHESIS: The primary outcome was the ratio of odds ratios (ROR), used to quantify the difference in estimated intervention effect between single-center and multicenter RCTs. An ROR less than 1 would indicate larger estimates of the intervention effect in single-center trials. Sensitivity analyses were performed with adjustment for sample size, risk of bias within RCTs, and variance of the log odds ratio to take publication bias into account. Forty-eight meta-analyses were selected, including 421 RCTs (223 were single-center and 198 were multicenter). Single-center RCTs showed a larger intervention effect than did multicenter RCTs (combined ROR, 0.73 [95% CI, 0.64 to 0.83]), with low heterogeneity across individual meta-analyses (I(2) = 12.0%; P = 0.24). Adjustment for sample size yielded consistent results (ROR, 0.85 [CI, 0.74 to 0.97]), as did adjustment for risk of bias within RCTs, such as allocation concealment (ROR, 0.76 [CI, 0.67 to 0.86]), and variance of log odds ratio (ROR, 0.83 [CI, 0.72 to 0.96]). LIMITATION: Despite sensitivity analyses, meta-confounding cannot be fully excluded. CONCLUSION: Single-center RCTs showed larger treatment effects than did multicenter RCTs, a finding that was consistent in all sensitivity analyses. These results suggest that this item should be considered when the results of RCTs and meta-analyses are interpreted. PRIMARY FUNDING SOURCE: Academic grant Recherche sur la Recherche from the Délégation Interrégionale à la Recherche Clinique (DIRC), Ile de France, Assistance Publique-Hôpitaux de Paris (APHP).

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Crossref · 10.7326/0003-4819-155-1-201107050-00006

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Research works printed but not linked: 4

  1. van Rijen M, 2008, Cochrane Database Syst Rev, CD006216
  2. Martin-Rendon E, 2008, Cochrane Database Syst Rev, CD006536
  3. Prasad K, 2008, Cochrane Database Syst Rev, CD000200
  4. von Elm E, 2008, Swiss Med Wkly, 138, 197

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Metadata

Authors
Dechartres, A., Boutron, I., Trinquart, L., Charles, P., & Ravaud, P.
Affiliations
  • From U738 INSERM; Assistance Publique Hôpitaux de Paris (APHP), Hôpital Hôtel-Dieu; Université Paris Descartes, Sorbonne Paris Cité, Faculté de Médecine; and French Cochrane Centre, Paris, France, and Hôpital Foch, Suresnes, France.
  • Inserm (FR)
ORCID
Venue
Annals of Internal Medicine
Publisher
American College of Physicians
Published
2011-07-05
Volume
155
Issue
1
Pages
39-51
ISSN
  • 0003-4819 (ISSN-L)
  • 1539-3704
DOI
10.7326/0003-4819-155-1-201107050-00006
OpenAlex
W2072619571
Cited by
307
References
72
Citations by year
2026: 14 · 2025: 16 · 2024: 22 · 2023: 19 · 2022: 37 · 2021: 27 · 2020: 14 · 2019: 16 · 2018: 13 · 2017: 22 · 2016: 24 · 2015: 19 · 2014: 23 · 2013: 20 · 2012: 19
FWCI
21.79
Type
journal article
Language
en
Open access
closed
Licence
www.acpjournals.org/journal/aim/text-and-data-mining (tdm)
Locations
  • Annals of Internal Medicine (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 Clinical Trials
  • Health Sciences › Nursing › Issues, ethics and legal aspects › Pharmaceutical industry and healthcare
Keywords
single-center trials, treatment effect estimates, meta-epidemiology, publication bias, allocation concealment, risk of bias, binary outcomes, sample size adjustment
MeSH terms
Humans, Sensitivity and Specificity, Meta-Analysis as Topic, Multicenter Studies as Topic, Epidemiologic Research Design, Bias, Odds Ratio, Randomized Controlled Trials as Topic, Treatment Outcome, Sample Size

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