km.coxph.plot {survcomp} | R Documentation

## Function to plot several Kaplan-Meier survival curves

### 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)

[Package survcomp version 1.40.0 Index]