Practical methods for incorporating summary time-to-event data into meta-analysis.
Open accessAbstract
BACKGROUND: In systematic reviews and meta-analyses, time-to-event outcomes are most appropriately analysed using hazard ratios (HRs). In the absence of individual patient data (IPD), methods are available to obtain HRs and/or associated statistics by carefully manipulating published or other summary data. Awareness and adoption of these methods is somewhat limited, perhaps because they are published in the statistical literature using statistical notation. METHODS: This paper aims to 'translate' the methods for estimating a HR and associated statistics from published time-to-event-analyses into less statistical and more practical guidance and provide a corresponding, easy-to-use calculations spreadsheet, to facilitate the computational aspects. RESULTS: A wider audience should be able to understand published time-to-event data in individual trial reports and use it more appropriately in meta-analysis. When faced with particular circumstances, readers can refer to the relevant sections of the paper. The spreadsheet can be used to assist them in carrying out the calculations. CONCLUSION: The methods cannot circumvent the potential biases associated with relying on published data for systematic reviews and meta-analysis. However, this practical guide should improve the quality of the analysis and subsequent interpretation of systematic reviews and meta-analyses that include time-to-event outcomes.
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Reviewers need the log hazard ratio and its standard error for a study to be included in a meta-analysis.
“Reviewers need the log hazard ratio and its standard error for a study to be included in a meta-analysis [111].”
From The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration (2009) · cites this paper as [111]
Methods are available for estimating the log hazard ratio and its standard error from other reported information.
“methods are available for estimating the desired quantities from other reported information [111].”
From The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration (2009) · cites this paper as [111]
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- Authors
- Tierney, J. F., Stewart, L. A., Ghersi, D., Burdett, S., & Sydes, M. R.
- Affiliations
- MRC Clinical Trials Unit at UCL (GB)
- University of York (GB)
- National Health and Medical Research Council (AU)
- Corresponding author
- Tierney, Jayne F
- Venue
- Trials
- Published
- 2007-06-07
- Volume
- 8
- Issue
- 1
- Pages
- 16-16
- ISSN
- 1745-6215 (ISSN-L)
- PMC
- PMC1920534
- OpenAlex
- W2088095316
- Cited by
- 6,208
- References
- 19
- Citations by year
- 2026: 243 · 2025: 311 · 2024: 403 · 2023: 482 · 2022: 563 · 2021: 665 · 2020: 584 · 2019: 491 · 2018: 467 · 2017: 485 · 2016: 397 · 2015: 344 · 2014: 246 · 2013: 206 · 2012: 108
- FWCI
- 36.82
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- Trials (publishedVersion)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- UCL Discovery (University College London) (submittedVersion)
- Funders
- Medical Research Council
- Australian 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
- time-to-event data, hazard ratio, meta-analysis, summary data, individual patient data, survival analysis, spreadsheet calculations, trial reports
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