Calculator for survival probability (the Kaplan-Meier method)
20 years ( other time interval such as month, etc can be substituted) This calculator works off-line. (IE4)

Number in trial=
Year Number died Number censored Survival probalility 95% confidence interval Number surviving
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To provide a more sophisticated graph using a spreadsheet such as Excel the results are provided as numbers in a comma delineated "flat file". This can be saved to disk from the webpage as a text file. The text file can then be imported into the spreadsheet. A permanent record of the analysis can be obtained by printing the page.

Programme written by DJR Hutchon.

This calculator is for educational use. It is believed accurate but no responsibility for accuracy of the results is accepted by the author. David J R Hutchon BSc, MB, ChB, FRCOG Consultant Gynaecologist, Memorial Hospital, Darlington, England. I am extremely grateful to my son Christopher J Hutchon B.Sc(Hons) for help in producing the graphs.
You are welcome to keep this page and use the calculator off-line. I would appreciate an E-mail if you find it useful enough to do so. E-mail to me at DJRHutchon@Postmaster.co.uk

Reference
Bland M J and Altman D G. Survival probabilities (the Kaplan-Meier method) British Medical Journal (1998) 317 1572
LINKS TO BMJ article e-journal Martin J GArdner and Douglas G Altman Statistics with confidence BMJ 1989 Ch 7

LINKS TO My home page