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Review
. 1999 Dec 4;319(7223):1492-5.
doi: 10.1136/bmj.319.7223.1492.

Calculating the number needed to treat for trials where the outcome is time to an event

D G Altman  1 , P K Andersen
Affiliations
Review

Calculating the number needed to treat for trials where the outcome is time to an event

D G Altman et al. BMJ. .
No abstract available

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Figures

Figure 1
Figure 1
Kaplan-Meier plots of survival for 164 patients with non-small lung cancer treated with radiotherapy plus chemotherapy versus radiotherapy alone
Figure 2
Figure 2
Number needed to treat to either benefit or harm with 95% confidence interval by time since treatment for 164 patients with non-small cell lung cancer treated with radiotherapy plus chemotherapy versus radiotherapy alone9 on basis of Cox regression model including only treatment
See this image and copyright information in PMC

References

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    1. Sackett DL, Richardson WS, Rosenberg W, Haynes RB. Evidence-based medicine. How to practice and teach EBM. London: Churchill Livingstone; 1997. pp. 136–141. , 168-70.
    1. Sackett DL, Haynes RB, Guyatt GH, Tugwell P. Clinical epidemiology: a basic science for clinical medicine, 2nd ed. Boston: Little Brown; 1991. p. 208.
    1. Altman DG, De Stavola BL, Love SB, Stepniewska KA. Review of survival analyses published in cancer journals. Br J Cancer. 1995;72:511–518. - PMC - PubMed
    1. Medical Research Council Rectal Cancer Working Party. Randomised trial of surgery alone versus radiotherapy followed by surgery for potentially operable locally advanced rectal cancer. Lancet. 1996;348:1605–1610. - PubMed

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