PROC LIFETEST: ODS Graphics :: SAS/STAT(R) 9.3 User's Guide

ODS Graphics

Statistical procedures use ODS Graphics to create graphs as part of their output. ODS Graphics is described in detail in Chapter 21, Statistical Graphics Using ODS.

Before you create graphs, ODS Graphics must be enabled (for example, with the ODS GRAPHICS ON statement). For more information about enabling and disabling ODS Graphics, see the section Enabling and Disabling ODS Graphics in Chapter 21, Statistical Graphics Using ODS.

The overall appearance of graphs is controlled by ODS styles. Styles and other aspects of using ODS Graphics are discussed in the section A Primer on ODS Statistical Graphics in Chapter 21, Statistical Graphics Using ODS.

The survival plot is produced by default; other graphs are produced by using the PLOTS= option in the PROC LIFETEST statement. You can reference every graph produced through ODS Graphics with a name. The names of the graphs that PROC LIFETEST generates are listed in Table 51.6, along with the required keywords for the PLOTS= option.

Table 51.6 Graphs Produced by PROC LIFETEST
ODS Graph Name	Plot Description	PLOTS=Option
DensityPlot	Estimated density for life-table method	PDF
FailurePlot	Estimated failure function	SURVIVAL(FAILURE)
HazardPlot	Estimated hazard function for life-table method or smoothed hazard for product-limit, Breslow, or Fleming-Harrington method	HAZARD
LogNegLogSurvivalPlot	Log of negative log of the estimated survivor function	LOGLOGS
NegLogSurvivalPlot	Negative log of the estimated survivor function	LOGSURV
SurvivalPlot	Estimated survivor function	SURVIVAL
SurvivalPlot	Estimated survivor function with number of subjects at risk	SURVIVAL(ATRISK=)
SurvivalPlot	Estimated survivor function with pointwise confidence limits	SURVIVAL(CL)
SurvivalPlot	Estimated survivor function with equal-precision band	SURVIVAL(CB=EP)
SurvivalPlot	Estimated survivor function with Hall-Wellner band	SURVIVAL(CB=HW)
SurvivalPlot	Estimated survivor function with homogeneity test p-value	SURVIVAL(TEST)

Additional Dynamic Variables for Survival Plots Using ODS Graphics

PROC LIFETEST passes a number of summary statistics as dynamic variables to the ODS Graphics for survival plots. Table 51.7 and Table 51.8 list these additional dynamic variables for the Kaplan-Meier curves and the life-table curves, respectively. These dynamic variables are not declared in the templates for the survival curves, but you can declare them and use them to enhance the default plots. The names of the dynamic variables depend on the STRATA= suboption of the PLOTS=SURVIVAL option: STRATA=INDIVIDUAL produces a separate plot for each stratum, and STRATA=OVERALL produces one plot with overlaid curves.

Table 51.7 Additional Dynamic Variables for **`Stat.Graphics.ProductLimitSurvival`**
STRATA=	Dynamic	Description
OVERLAY	StrVal $\text{[math]}$	Label for the $\text{[math]}$ th stratum
	NObs $\text{[math]}$	Number of observations in the $\text{[math]}$ th stratum
	NEvent $\text{[math]}$	Number of events in the $\text{[math]}$ th stratum
	Median $\text{[math]}$	Median survival time of the $\text{[math]}$ th stratum
	LowerMedian $\text{[math]}$	Lower median survival time of the $\text{[math]}$ th stratum
	UpperMedian $\text{[math]}$	Upper median survival time of the $\text{[math]}$ th stratum
	PctMedianConfid	Confidence of the median intervals in percent
INDIVIDUAL	NObs	Number of observations
	NEvent	Number of events
	Median	Median survival time
	LowerMedian	Lower median survival time
	UpperMedian	Upper median survival time
	PctMedianConfid	Confidence of the median interval in percent

Table 51.8 Additional Dynamic Variables for **`Stat.Graphics.LifetableSurvival`**
STRATA=	Dynamic	Description
OVERLAY	StrVal $\text{[math]}$	Label for the $\text{[math]}$ th stratum
	NObs $\text{[math]}$	Number of observations in the $\text{[math]}$ th stratum
	NEvent $\text{[math]}$	Number of events in the $\text{[math]}$ th stratum
INDIVIDUAL	NObs	Number of observations
	NEvent	Number of events

See the section The Graph Template Language in Chapter 22, ODS Graphics Template Modification, for the general use of dynamic variables. For the use of the particular dynamic variables shown in this section, see the sections Modifying the Layout and Adding a New Inset Table and Displaying Survival Summary Statistics in Chapter 22, ODS Graphics Template Modification.

The LIFETEST Procedure

Additional Dynamic Variables for Survival Plots Using ODS Graphics