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 ------------------------------------------------------------------------- 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) -------------------------------------------------------------------------

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