You can specify the OUTSURV= option in the PROC LIFETEST statement to create an output data set that contains the survival estimates. The data set contains the following columns:
any specified BY variables
a numeric variable STRATUM
that numbers the strata, if you specify the STRATA statement
any specified STRATA variables, their values coming from either their original values or the midpoints of the stratum intervals if endpoints are used to define strata (semi-infinite intervals are labeled by their finite endpoint)
the GROUP= variables, if you specify the GROUP= option in the STRATA statement
the time variable as specified in the TIME statement. For METHOD=KM, METHOD=BRESLOW, or METHOD=FH, it contains the observed failure or censored times. For the life-table estimates, it contains the lower endpoints of the time intervals.
SURVIVAL
, a variable that contains the survivor function estimates
CONFTYPE
, a variable that contains the name of the transformation applied to the survival time in the computation of confidence intervals
SDF_LCL
, a variable that contains the lower limits of the pointwise confidence intervals for the survivor function
SDF_UCL
, a variable that contains the upper limits of the pointwise confidence intervals for the survivor function
If the estimation uses the product-limit, Breslow, or Fleming-Harrington method, then the data set also contains the following:
_CENSOR_
, an indicator variable that has a value 1 for a censored observation and a value 0 for an event observation
SDF_STDERR
, a variable that contains the standard error of the survivor function estimator
HW_LCL
, a variable that contains the lower limits of the Hall-Wellner confidence bands (if you specify the CONFBAND=HW option or
the CONFBAND=ALL option in the PROC LIFETEST statement)
HW_UCL
, a variable that contains the upper limits of the Hall-Wellner confidence bands (if you specify the CONFBAND=HW option or
the CONFBAND=ALL option in the PROC LIFETEST statement)
EP_LCL
, a variable that contains the lower limits of the equal-precision confidence bands (if you specify the CONFBAND=EP option
or the CONFBAND=ALL option in the PROC LIFETEST statement)
EP_UCL
, a variable that contains the upper limits of the equal-precision confidence bands (if you specify the CONFBAND=EP option
or the CONFBAND=ALL option in the PROC LIFETEST statement)
If the estimation uses the life-table method, then the data set also contains the following:
MIDPOINT
, a variable that contains the value of the midpoint of the time interval
PDF
, a variable that contains the density function estimates
PDF_LCL
, a variable that contains the lower endpoints of the PDF confidence intervals
PDF_UCL
, a variable that contains the upper endpoints of the PDF confidence intervals
HAZARD
, a variable that contains the hazard estimates
HAZ_LCL
, a variable that contains the lower endpoints of the hazard confidence intervals
HAZ_UCL
, a variable that contains the upper endpoints of the hazard confidence intervals
Each survival function contains an initial observation with the value 1 for the SDF and the value 0 for the time. The output data set contains an observation for each distinct failure time if the product-limit, Breslow, or Fleming-Harrington method is used, or it contains an observation for each time interval if the life-table method is used. The product-limit, Breslow, or Fleming-Harrington survival estimates are defined to be right continuous; that is, the estimates at a given time include the factor for the failure events that occur at that time.