Nelson-Aalen Estimator of the Cumulative Hazard in Multistate Models.

mvna

The R package mvna (multivariate Nelson-Aalen estimator) permits to estimate non-parametrically the cumulative transition hazards of arbitrary Markov multi-state models using the Nelson-Aalen estimator.

Installation

You can download the stable version on CRAN

install.packages("mvna")

Or you can install the development version from github

## if necessary
## install.packages("devtools")
devtools::install_github("aallignol/mvna")

Usage

library(mvna)
data(sir.cont)

# Matrix of possible transitions
tra <- matrix(ncol=3,nrow=3,FALSE)
tra[1, 2:3] <- TRUE
tra[2, c(1, 3)] <- TRUE

# Modification for patients entering and leaving a state
# at the same date
sir.cont <- sir.cont[order(sir.cont$id, sir.cont$time), ]
for (i in 2:nrow(sir.cont)) {
  if (sir.cont$id[i]==sir.cont$id[i-1]) {
    if (sir.cont$time[i]==sir.cont$time[i-1]) {
      sir.cont$time[i-1] <- sir.cont$time[i-1] - 0.5
    }
  }
}

# Computation of the Nelson-Aalen estimates
  na.cont <- mvna(sir.cont,c("0","1","2"),tra,"cens")

if (require("lattice")) {
  xyplot(na.cont,tr.choice=c("0 2","1 2"),aspect=1,
       strip=strip.custom(bg="white",
         factor.levels=c("No ventilation -- Discharge/Death",
           "Ventilation -- Discharge/Death"),
         par.strip.text=list(cex=0.9)),
       scales=list(alternating=1),xlab="Days",
       ylab="Nelson-Aalen estimates")
}