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Cited by 2,305Meta-analysis and systematic reviewsStatistical Methods in Clinical TrialsStatistical Methods in Epidemiology

The DOI matches its Crossref record; 37 of the 37 references it cites were found in a registry or an index.

Meta-analyses involving cross-over trials: methodological issues

Elbourne, Diana R, Altman, Douglas G, Higgins, Julian PT, Curtin, Francois, Worthington, Helen V, Vail, Andy·2002·International Journal of Epidemiology
DOI 10.1093/ije/31.1.140
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Abstract

BACKGROUND: Meta-analysis of randomized controlled trials (RCTs) is usually based on trials where patients are randomized individually into two different, parallel, treatment groups. This paper concentrates on RCTs of a different design-two-period, two-treatment cross-over trials. METHODS: The characteristics of these trials are outlined, with detailed examples of methods for analysis for both continuous and binary data. These case studies are then extended into the context of a meta-analysis. The Cochrane Library was surveyed to assess current practice for synthesis. RESULTS: Methods are described for continuous and binary data for use both when the necessary paired data are given and also when they need to be calculated or imputed, and some suggestions are provided to help people wishing to synthesize data from cross-over trials into meta-analyses. The survey suggested that about 8% of the trials in the Cochrane library were cross-over trials and 18% of the reviews referred to such trials, although there was no consistent approach to their inclusion into the reviews. CONCLUSIONS: Methods do exist for including valuable information from two-period, two-treatment cross-over trials into quantitative reviews. However, poor reporting of cross-over trials will often impede attempts to perform a meta-analysis using the available methods.

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Research works printed but not linked: 5

  1. Daya S. Differences between crossover and parallel study designs—debate? Fertil Steril1999;71:771–72.
  2. Morris JA, Gardner MJ. Epidemiological studies. In: Altman DG, Machin D, Bryant TN, Gardner MJ (eds). Statistics with Confidence. 2nd Edn. London: BMJ Books, 2000, pp.57–72.
  3. Jennings AL, Davies A, Higgins JPT, Broadley K. Opioids for the palliation of breathlessness in terminal illness (Cochrane review). In: The Cochrane Library, Issue 4, 2001. Oxford: Update Software, 2001.
  4. Cochrane Collaboration. The Cochrane Library. Issue 1. Oxford: Update Software, 2001.
  5. Smyth A, Walters S. Prophylactic antibiotics for cystic fibrosis (Cochrane Review). In: The Cochrane Library, Issue 1, 2001. Oxford: Update Software. Updated quarterly.

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Metadata

Authors
Elbourne, D. R., Altman, D. G., Higgins, J. P., Curtin, F., Worthington, H. V., & Vail, A.
Affiliations
  • London School of Hygiene & Tropical Medicine (GB)
  • Merck KGaA, Darmstadt (Germany) (DE)
  • University Dental Hospital of Manchester (GB)
  • Salford Royal Hospital (GB)
Corresponding author
Elbourne, Diana R
ORCID
Venue
International Journal of Epidemiology
Publisher
Oxford University Press (OUP)
Published
2002-02
Volume
31
Issue
1
Pages
140-149
ISSN
  • 0300-5771 (ISSN-L)
  • 1464-3685
DOI
10.1093/ije/31.1.140
OpenAlex
W2130235475
Cited by
2,305
References
37
Citations by year
2026: 58 · 2025: 58 · 2024: 72 · 2023: 87 · 2022: 116 · 2021: 129 · 2020: 107 · 2019: 111 · 2018: 128 · 2017: 131 · 2016: 145 · 2015: 147 · 2014: 174 · 2013: 135 · 2012: 144
FWCI
47.29
Type
journal article
Language
en
Open access
closed
Locations
  • International Journal of Epidemiology (publishedVersion)
  • PubMed (publishedVersion)
  • Research Explorer (The University of Manchester) (submittedVersion)
Funders
Medical Research Council
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
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
Keywords
crossover trial, meta-analysis, randomized controlled trials, continuous data, binary data, missing data imputation, trial reporting quality, Cochrane Library
MeSH terms
Humans, Review Literature as Topic, Meta-Analysis as Topic, Randomized Controlled Trials as Topic, Cross-Over Studies

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