RMvsKM {nnt}

Compare the performance between the NNT-RMST and NNT-KM through the average life gain per patient

Description

For the NNT-RMST, the average life gain per patient is the area between the survival curves, which is the instrinsic treatment benefit in survival time during the t-period follow-up. For the NNT-KM, the average life gain per patient is defined as the ratio between the average survival time of one death in patients and the NNT-KM up to t.

Usage

RMvsKM(time, status, arm, tau = NULL, confint = 0.95, digits = 3)

Arguments

time

The time to event or censor.

status

The indicator of the event or censor at the end of the follow-up.

arm

The variable indicates the treatment (arm = 1) and control (arm = 0) groups.

tau

The chosen time point of clinical interest.

confint

The percentile of confidence interval. The default value is confint = 0.95.

digits

The decimal of the results. The default value is digits = 3.

Value

A list contains:

RMSTNNT

The RMST-NNT and its confidence interval.

KMNNT

The KM-NNT and its confidence interval.

LifeGain

The average life gain per patient based on the RMST-NNT and KM-NNT.

References

1. An alternative approach for estimating the number needed to treat for survival endpoints. PLoS One. 2019 Oct 18;14(10):e0223301. doi: 10.1371/journal.pone.0223301.

Examples

library(survival)
dat <- pbc[!is.na(pbc$trt),]
time <- dat$time/365.25
status <- (dat$status == 2) + 0
arm <- (dat$trt == 2) + 0
RMvsKM(time, status, arm, tau = NULL, confint = 0.95, digits = 3)