logrank: The Log-rank test

In eha: Event History Analysis

The Log-rank test

Description

Performs the log-rank test on survival data, possibly stratified.

Usage

logrank(Y, group, data = parent.frame())

Arguments

Y	a survival object as returned by the Surv function.
group	defines the groups to be compared. Coerced to a factor.
data	a data.frame in which to interpret the variables.

Value

A list of class logrank with components

test.statistic	The logrank (score) test statistic.
df	The degrees of freedom of the test statistic.
p.value	The p value of the test.
hazards	A list of two-column matrices, describing event times and corresponding hazard atoms in each stratum (class 'hazdata').
call	The call

Note

The test is performed by fitting a Cox regression model and reporting its score test. With tied data, this might be slightly different from the true logrank test, but the difference is unimportant in practice.

Author(s)

Göran Broström

See Also

coxreg, print.logrank.

Examples

fit <- logrank(Y = Surv(enter, exit, event), group = civ, 
data = oldmort[oldmort$region == "town", ])
fit

eha documentation built on Oct. 7, 2024, 1:17 a.m.