kmest {trtswitch} | R Documentation |
Kaplan-Meier Estimates of Survival Curve
Description
Obtains the Kaplan-Meier estimates of the survival curve.
Usage
kmest(
data,
rep = "",
stratum = "",
time = "time",
event = "event",
conftype = "log-log",
conflev = 0.95,
keep_censor = 0L
)
Arguments
data |
The input data frame that contains the following variables:
|
rep |
The name(s) of the replication variable(s) in the input data. |
stratum |
The name(s) of the stratum variable(s) in the input data. |
time |
The name of the time variable in the input data. |
event |
The name of the event variable in the input data. |
conftype |
The type of the confidence interval. One of "none", "plain", "log", "log-log" (the default), or "arcsin". The arcsin option bases the intervals on asin(sqrt(survival)). |
conflev |
The level of the two-sided confidence interval for the survival probabilities. Defaults to 0.95. |
keep_censor |
Whether to retain the censoring time in the output data frame. |
Value
A data frame with the following variables:
-
size
: The number of subjects in the stratum. -
time
: The event time. -
nrisk
: The number of subjects at risk. -
nevent
: The number of subjects having the event. -
ncensor
: The number of censored subjects. -
survival
: The Kaplan-Meier estimate of the survival probability. -
stderr
: The standard error of the estimated survival probability based on the Greendwood formula. -
lower
: The lower bound of confidence interval if requested. -
upper
: The upper bound of confidence interval if requested. -
conflev
: The level of confidence interval if requested. -
conftype
: The type of confidence interval if requested. -
stratum
: The stratum. -
rep
: The replication.
Author(s)
Kaifeng Lu, kaifenglu@gmail.com
Examples
kmest(data = aml, stratum = "x", time = "time", event = "status")