help stsurvdiff 
                                                        also see:  sts generate
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Title

    stsurvdiff -- Difference between two Kaplan-Meier survival curves


Syntax

        stsurvdiff varname [if] [in] [, options]


    options                        Description
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      generate(stubname)           defines the stub-name for variables
                                     containing results created by stsurvdiff
      level(#)                     sets the confidence level of the CI for
                                     the difference in survival curves
      smooth                       smooths the difference and its standard
                                     error as a function of time (_t)
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    You must stset your data before using stsurvdiff; see [ST] stset.


Description

    stsurvdiff computes the difference in the Kaplan-Meier survival curves,
    and a pointwise confidence interval, at the two levels of a binary
    "treatment" variable, varname.


Options

    generate(stubname) defines the stub-name for variables containing results
        created by stsurvdiff. For example, if stubname is diff, four new
        variables are created, with names diff, diff_se, diff_lci and
        diff_uci, respectively.

    level(#) specifies the percent confidence level for the pointwise
        confidence interval of the difference in survival functions. The
        default # is 95%.

    smooth applies a running-line smooth (see running) to the difference in
        survival curves and its standard error.


Examples

        . stsurvdiff treat
        . stsurvdiff treat, generate(diff) level(99) smooth


Author

    Patrick Royston, MRC Clinical Trials Unit, London, UK.  (
    pr@ctu.mrc.ac.uk)


Also see