Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2007 Jun 7:8:16.
doi: 10.1186/1745-6215-8-16.

Practical methods for incorporating summary time-to-event data into meta-analysis

Jayne F Tierney  1 , Lesley A Stewart, Davina Ghersi, Sarah Burdett, Matthew R Sydes
Affiliations

Practical methods for incorporating summary time-to-event data into meta-analysis

Jayne F Tierney et al. Trials. .

Abstract

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.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Bladder cancer trial Kaplan-Meier plot (modified with permission [6]), schematically divided into time intervals for data extraction into Table 2.
Figure 2
Figure 2
Data input screens (A, B and D), generated curves (C and E) and output screen (F) from the calculations spreadsheet.
See this image and copyright information in PMC

Comment in

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Parmar MKB, Torri V, Stewart L. Extracting summary statistics to perform meta-analyses of the published literature for survival endpoints. Statistics in Medicine. 1998;17:2815–34. doi: 10.1002/(SICI)1097-0258(19981230)17:24<2815::AID-SIM110>3.0.CO;2-8. - DOI - PubMed
    1. Williamson PR, Tudur Smith C, Hutton JL, Marson AG. Aggregate data meta-analysis with time-to-event outcomes. Statistics in Medicine. 2002;21:3337–51. doi: 10.1002/sim.1303. - DOI - PubMed
    1. Altman DG, De Stavola BL, Love SB, Stepniewska KA. Review of survival analyses published in cancer. British Journal of Cancer. 1995;72:511–8. - PMC - PubMed
    1. Pocock SJ, Clayton TC, Altman DG. Survival plots of time-to-event ouctomes in clinical trials. Lancet. 2002;359:1686–9. doi: 10.1016/S0140-6736(02)08594-X. - DOI - PubMed
    1. Mangioni C, Bolis G, Pecorelli S, Bragman K, Epis A, Favalli G, Gambino A, Landoni F, Presti M, Torri W, Vassena L, Zanaboni F, Marsoni S. Randomized trial in advanced ovarian cancer comparing cisplatin and carboplatin. Journal of the National Cancer Institute. 1989;81:1461–71. doi: 10.1093/jnci/81.19.1464. - DOI - PubMed

LinkOut - more resources