swh:1:snp:ff0951ca787d0b7f47dc2335f47fed43820a6324
Tip revision: 9192c6321466db058b8999b903de69a587f6556b authored by Venkatraman E. Seshan on 07 March 2023, 00:00:02 UTC
version 1.1.1
version 1.1.1
Tip revision: 9192c63
coxphERR.Rd
\name{coxphERR}
\title{Heller Explained Relative Risk}
\alias{coxphERR}
\keyword{survival}
\description{
Calculates the contribution of a subset of covariates to the explained
relative risk derived from the full Cox proportional hazards model.
}
\usage{
coxphERR(phfit, ngamma=NULL)
}
\arguments{
\item{phfit}{The output from a proportional hazards fit.}
\item{ngamma}{A vector of indices corresponding to covariates of
interest. If missing (default), the explained relative risk is
computed for the full model.}
}
\value{
The function coxphERR returns the vector (ERR, se.ERR).
The first component ERR represents the contribution of a subset of
covariates to the explained relative risk estimate of the full
model. If a set of covariates is not provided, then it computes the
estimate of the full model. The second component se.ERR is the
standard error of the estimate.
}
\details{
The object phfit should be the result of a call to coxph with the
option x=TRUE.
}
\examples{
\dontrun{
library(survival)
ovarianfit <- coxph(Surv(futime, fustat) ~ age + resid.ds + rx +
ecog.ps, data=ovarian,x=T)
# Compute the explained relative risk (ERR) and
# its standard error (se.ERR) for the full model.
coxphERR(ovarianfit)
# Compute the contribution of age and ECOG performance status to
# the explained relative risk. Age and ECOG performance status are
# the first and fourth covariates in the model.
coxphERR(ovarianfit, c(1,4))
}}
\references{
Heller G. (2012) A measure of explained risk in the proportional hazards
model. \emph{Biostatistics}
}