This function just calls Surv() from the
survival
package.
Surv(time, time2, event, type = c("right", "left", "interval", "counting",
"interval2"), origin = 0)for right censored data, this is the follow up time. For interval data, the first argument is the starting time for the interval.
ending time of the interval for interval censored or counting
process data only. Intervals are assumed to be open on the left and
closed on the right, (start, end]. For counting process
data, event indicates whether a transtion to another state
occurred at the end of the interval.
The status indicator, normally 0=alive, 1=dead. Other choices are
TRUE/FALSE (TRUE = death), 1/2 (2=death), or
a factor variable.
For interval censored data, the status indicator is 0=right censoed,
1=event at time, 2=left censored, 3=interval censored.
For multiple endpoint data the event variable will always be a factor,
whose first level is treated as censoring, or more formally
"no transtition at this time point".
There is no constraint on the labels of the factor.
Although unusual, the event indicator can be omitted, in which case
all subjects are assumed to have an event.
character string specifying the type of censoring. Possible values
are "right", "left", "counting",
"interval", "interval2". The default is multi-state
if event is a factor, counting process if time2 is
present, or right censored, in that order.
for counting process data, the hazard function origin. This option was intended to be used in conjunction with a model containing time dependent strata in order to align the subjects properly when they cross over from one strata to another, but it has rarely proven useful and is depricated.