hazard.ratio {survcomp} | R Documentation

## Function to estimate the hazard ratio through Cox regression

### Description

Function to compute the hazard ratio for a risk prediction.

### Usage

    hazard.ratio(x, surv.time, surv.event, weights, strat, alpha = 0.05,
    method.test = c("logrank", "likelihood.ratio", "wald"), na.rm = FALSE, ...)

### Arguments

`x` | a vector of risk predictions.
`surv.time` | a vector of event times.
`surv.event` | a vector of event occurrence indicators.
`weights` | weight of each sample.
`strat` | stratification indicator.
`alpha` | apha level to compute confidence interval.
`method.test` | Statistical test to use in order to compute the p-values related to a D. index, see summary.coxph for more details.
`na.rm` | `TRUE` if missing values should be removed.
`...` | additional parameters to be passed to the `coxph` function.

### Details

The hazard ratio is computed using the Cox model.

### Value

`hazard.ratio` | hazard ratio estimate.
`coef` | coefficient (beta) estimated in the cox regression model.
`se` | standard error of the coefficient (beta) estimate.
`lower` | lower bound for the confidence interval.
`upper` | upper bound for the confidence interval.
`p.value` | p-value computed using the likelihood ratio test whether the hazard ratio is different from 1.
`n` | number of samples used for the estimation.
`coxm` | `coxph.object` fitted on the survival data and `x` (see below).
`data` | list of data used to compute the hazard ratio (`x`, `surv.time` and `surv.event`).

### Author(s)

Benjamin Haibe-Kains

### References

Cox, D. R. (1972) "Regression Models and Life Tables", Journal of the Royal Statistical Society Series B, 34, pages 187–220.

### See Also

`coxph`, `coxph.object`

### Examples

    set.seed(12345)
    age <- rnorm(100, 50, 10)
    stime <- rexp(100)
    cens   <- runif(100,.5,2)
    sevent  <- as.numeric(stime <= cens)
    stime <- pmin(stime, cens)
    strat <- sample(1:3, 100, replace=TRUE)
    weight <- runif(100, min=0, max=1)
    hazard.ratio(x=age, surv.time=stime, surv.event=sevent, weights=weight,
      strat=strat)

[Package survcomp version 1.40.0 Index]