PowFrailtyDat {PDXpower}R Documentation

A function to obtain a power table with the combination of various number of PDX lines and number of individuals per PDX lines per treatment based on a preliminary dataset

Description

A function to obtain a power table with the combination of various number of PDX lines and number of individuals per PDX lines per treatment based on a preliminary dataset

Usage

PowFrailtyDat(
  data = NULL,
  formula = NULL,
  maxit = 50,
  hazard = "Weibull",
  n = NULL,
  m = NULL,
  sim = 1000,
  censor = FALSE,
  Ct = 5,
  two.sided = TRUE,
  alpha = 0.05,
  fixed.effect = FALSE,
  digits = 4,
  ncores = NULL
)

Arguments

data

data.frame in which to interpret the variables named in the formula.

formula

a formula object, with the response on the left of a ~ operator, and the terms on the right. The response must be a survival object as returned by the Surv function.

maxit

maximum number of iterations needed for model fitting. Default is 50.

hazard

distributional assumption of the baseline hazard. Default is Weibull.

n

an integer number to specify the number of PDX lines.

m

an integer number to specify the number of individuals per PDX line per treatment.

sim

Number of Monte Carlo samples to be generated. Default is 1000.

censor

logical value of whether a censoring distribution is considered in a data generation setting. Default is FALSE.

Ct

a fixed time point when a study is designed to end for generating type 1 censoring data.

two.sided

A logical value to indicate if a two-sided hypothesis testing is conducted. Default is TRUE.

alpha

significance level. Default is 0.05.

fixed.effect

logical value to indicate if a fixed effects only model is fitted. Default is FALSE.

digits

digits the number of significant digits to use when printing.

ncores

number of cores for parallel computation.

Value

Object of PowFrailtyDat with elements

lambda

the estimated scale parameter of Weibull baseline hazard from the pilot data.

nu

the estimated shape parameter of Weibull baseline hazard from the pilot data.

beta

the estimated treatment effect from the pilot data.

tau2

the estimated inter-PDX variance from the pilot data.

sigma2

the estimated random error variance from the pilot data.

PowTab

the estimates of statistical power across n and m.

Examples


require(PDXpower)
data(animals2)
PowTab <- PowFrailtyDat(data = animals2, formula = Surv(Y,status) ~ Tx + cluster(ID),
n = 3, m = 2, ncores = 1)
PowTab
plotpower(PowTab[[5]], ylim = c(0, 1))



[Package PDXpower version 1.0.4 Index]