27.03.2013 Views

SPSS® 12.0 Command Syntax Reference

SPSS® 12.0 Command Syntax Reference

SPSS® 12.0 Command Syntax Reference

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

TEST Subcommand<br />

KM 793<br />

TEST specifies the test statistic to use for testing the equality of survival distributions for the<br />

different levels of the factor.<br />

• TEST is valid only when a factor variable is specified. If no factor variable is specified,<br />

KM issues a warning and TEST is not executed.<br />

• If TEST is specified without a keyword, the default is LOGRANK. If a keyword is specified<br />

on TEST, only the specified test is performed.<br />

• Each of the test statistics has a chi-square distribution with one degree of freedom.<br />

LOGRANK Perform the log rank (Mantel-Cox) test.<br />

BRESLOW Perform the Breslow (generalized Wilcoxon) test.<br />

TARONE Perform the Tarone-Ware test.<br />

COMPARE Subcommand<br />

COMPARE compares the survival distributions for the different levels of the factor. Each of<br />

the keywords specifies a different method of comparison.<br />

• COMPARE is valid only when a factor variable is specified. If no factor variable is specified,<br />

KM issues a warning and COMPARE is not executed.<br />

• COMPARE uses whatever tests are specified on the TEST subcommand. If no TEST subcommand<br />

is specified, the log rank test is used.<br />

• If COMPARE is not specified, the default is OVERALL and POOLED. All factor levels are<br />

compared across strata in a single test. The test statistics are displayed after the summary<br />

table at the end of output.<br />

• Multiple COMPARE subcommands can be specified to request different comparisons.<br />

OVERALL Compare all factor levels in a single test. OVERALL, together with POOLED,<br />

is the default when COMPARE is not specified.<br />

PAIRWISE Compare each pair of factor levels. KM compares all distinct pairs of factor<br />

levels.<br />

POOLED Pool the test statistics across all strata. The test statistics are displayed after<br />

the summary table for all strata. POOLED, together with OVERALL, is the<br />

default when COMPARE is not specified.<br />

STRATA Compare the factor levels for each stratum. The test statistics are displayed<br />

for each stratum separately.<br />

• If a factor variable has different levels across strata, you cannot request a pooled comparison.<br />

If you specify POOLED on COMPARE, KM displays a warning and ignores the request.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!