stipulates a competing-risks analysis, which consists of estimating cumulative incidence functions and computing Gray’s test
(Gray 1988) for testing the homogeneity of two or more cumulative incidence functions. You specify a number that represents the event
of interest after the equal sign. For example:

proc lifetest;
time T*Status(0) / failcode=1;
run;

For this specification, PROC LIFETEST regards a `Status`

value of 1 as the event of interest, a value of 0 as a censored observation indicator, and all other values as competing
events.

You can specify a list of values after the equal sign. PROC LIFETEST performs a separate competing-risks analysis for each
value, regarding it as representing the event of interest. For example:

proc lifetest;
time T*Status(0) / failcode=1 2;
run;

This specification produces two analyses, one for FAILCODE=1 and the other for FAILCODE=2.

If you specify the FAILCODE option without the equal sign, PROC LIFETEST produces a separate analysis for each distinct event
value. Consider a data set with an event indicator variable `Status`

that assumes four distinct values, 0, 1, 2, and 3, where `Status`

=0 represents observations that are censored and `Status`

=1, `Status`

=2, and `Status`

=3 represent three different causes of failure. Consider the following statements:

proc lifetest;
time T*Status(0) / failcode;
run;

PROC LIFETEST produces three separate competing-risks analyses: one uses Status=1 as the failure cause of interest, one uses
Status=2 as the failure cause of interest, and one uses Status=3 as the failure cause of interest. This specification is convenient
for an exploratory analysis when there is no predetermined failure cause of interest.