km.coxph.plot: Function to plot several Kaplan-Meier survival curves

In survcomp: Performance Assessment and Comparison for Survival Analysis

Description

Function to plot several Kaplan-Meier survival curves with number of individuals at risk at some time points.

Usage

km.coxph.plot(formula.s, data.s, weight.s, x.label, y.label, main.title, sub.title,
leg.text, leg.pos = "bottomright", leg.bty = "o", leg.inset = 0.05, o.text, v.line,
h.line, .col = 1:4, .lty = 1, .lwd = 1, show.n.risk = FALSE, n.risk.step,
n.risk.cex = 0.85, verbose = TRUE, ...)

Arguments

formula.s	formula composed of a Surv object and a strata variable (i.e. stratification).
data.s	data frame composed of the variables used in the formula.
weight.s	vector of weights of length nrow(data.s).
x.label	label for the y-axis.
y.label	label for the x-axis.
main.title	main title at the top of the plot.
sub.title	subtitle at the bottom of the plot.
leg.text	text in the legend.
leg.pos	the location may also be specified by setting 'x' to a single keyword from the list "bottomright", "bottom", "bottomleft", "left", "topleft", "top", "topright", "right" and "center". This places the legend on the inside of the plot frame at the given location.
leg.bty	the type of box to be drawn around the legend. The allowed values are "o" (the default) and "n".
leg.inset	inset distance from the margins as a fraction of the plot region. Default value is 0.05.
o.text	plot the logrank p-value.
v.line	x coordinate(s) for vertical line(s).
h.line	y coordinate(s) for horizontal line(s).
.col	vector of colors for the different survival curves.
.lty	vector of line types for the different survival curves
.lwd	vector of line widths for the different survival curves.
show.n.risk	if TRUE, show the numbers of samples at risk for each time step.
n.risk.step	vector specifying the time to be the steps for displaying the number of individuals at risk.
n.risk.cex	size of the number of individuals at risk. Default value is 0.85.
verbose	verbosity level (TRUE or FALSE). Default value is TRUE.
...	additional parameters to be passed to the plot function.

Details

The original version of this function was kindly provided by Dr Christos Hatzis (January, 17th 2006).

Value

Several Kaplan-Meier survival curves with number of individuals at risk at some time points.

Author(s)

Christos Hatzis, Benjamin Haibe-Kains

See Also

survfit, coxph

Examples

set.seed(12345)
stime <- rexp(100) * 10
cens   <- runif(100,.5,2) * 10
sevent  <- as.numeric(stime <= cens)
stime <- pmin(stime, cens)
strat <- sample(1:3, 100, replace=TRUE)
dd <- data.frame("surv.time"=stime, "surv.event"=sevent, "strat"=strat)
ddweights <- array(1, dim=nrow(dd))

km.coxph.plot(formula.s=Surv(surv.time, surv.event) ~ strat, data.s=dd,
  weight.s=ddweights, x.label="Time (years)", y.label="Probability of survival",
  main.title="", leg.text=paste(c("Low", "Intermediate", "High"), "   ", sep=""),
  leg.pos="topright", leg.inset=0, .col=c("darkblue", "darkgreen", "darkred"),
  .lty=c(1,1,1), show.n.risk=TRUE, n.risk.step=2, n.risk.cex=0.85, verbose=FALSE)

Example output

Loading required package: survival
Loading required package: prodlim

survcomp documentation built on Nov. 8, 2020, 4:54 p.m.