wmst_pow: Sample Size and Power for the Test of the Difference in...
In pauknemj/survWM2: Survival Analysis with Window Mean Survival Time

wmst_pow

R Documentation

Sample Size and Power for the Test of the Difference in Window Mean Survival Time

Description

Determine the asymptotic power of the test of WMST under a given trial design, or calculate the samples size needed to achieve a desired power.

Usage

wmst_pow(survC, survT, censor = NA, eperiod, end_study, tau0, tau1, n = NA, power = NA, plot = FALSE, sim = F, M = 1000, method = "tau_star", alpha = 0.05, two.sided = FALSE)

Arguments

`survC`	the survival distribution of the control group, as a list in the form output by `wmst_surv`.
`survT`	the survival distribution of the treatment group, as a list in the form output by `wmst_surv`.
`censor`	The common CDF of the censoring distribution for treatment and control arms.
`eperiod`	The duration of the enrollment period if subjects are assumed to accrue uniformly over the enrollment interval `⁠(0,eperiod)⁠`.
`end_study`	The total duration of the study/follow-up period.
`tau0`	A scaler vector to specify the lower truncation time points of the window for the WMST calculation. `tau0` needs to be at least 0 and smaller than tau1. When `tau0 = NULL`, the default value 0 is used (i.e., the lower bound for restricted mean survival analysis).
`tau1`	A scaler value to specify the upper truncation time point of the window for the WMST calculation. `tau1` needs to be smaller than the minimum of the largest observed time in each of the two groups. When `tau1 = NULL`, the default value (i.e., the minimum of the largest observed time in each of the two groups) is used.
`n0`	The total sample size in control group.
`n1`	The total sample size in treatment group.
`power`	The desired power of the test.
`alpha`	The type I error level. Default is 0.05.
`two.sided`	Determines whether the test is upper-tailed (`two.sided` = FALSE) or two-sided. The default is FALSE.

Details

For more details, please see the package vignette: browseVignettes(package = "survWMST")

Value

an object of class pow.

`n`	the user-specified n, or if n was left blank, the n needed to achieve the user-specified power.
`powerWMST`	the user-specified power, or if power was left blank, the asymptotic power of the RMST test. If `two.sided=FALSE`, `powerWMST` gives the power of rejecting in favor of the treatment arm. If `two.sided=TRUE`, `powerWMST` gives the power of rejecting the null in favor of a two-sided alternative.