OneArm2stage (version 1.2.1)

FitDat: Fit Historical Survival Data Assuming the Failure Time Follows a Weibull Distribution

Description

The function fits parametric models for the time-to-event data with the underlying distribution of the failure time assumed to be Weibull.

Usage

FitDat(data)

Value

fit.Weibull the fitted model assuming a Weibull distribution.

AIC the AIC value from the fitted model.

parameter.estimates the estimated parameters from the fitted model.

Arguments

data

a historical survival data sample, has to contain two variables 'Time' and 'Cens':
Time, the time under observation during trial for each patient.
Cens, the status indicator of patients (event = 1, censored = 0).

References

Wang, M., Rule, S., Zinzani, P. L., Goy, A., Casasnovas, O., Smith, S. D.,..., Robak, T. (2018). Acalabrutinib in relapsed or refractory mantle cell lymphoma (ACE-LY-004): a single-arm, multicentre, phase 2 trial. The Lancet, 391(10121), 659–667. https://doi.org/10.1016/s0140-6736(17)33108-2

Examples

library(IPDfromKM)
# a sample dataset that we already extracted from Wang et al, 2018.
df<- read.csv(system.file("extdata", "df.csv", package = "OneArm2stage"))

# risk time points
trisk <- c(0,2,4,6,8,10,12,14,16,18,20,22,24)

# number of patients at risk at each risk time point
nrisk.radio <- c(124,120,115,110,107,104,103,95,46,18,11,8,0)

# Preprocess the raw coordinates into an proper format for reconstruct IPD
pre_radio <- preprocess(dat=df, trisk=trisk,
                     nrisk=nrisk.radio,totalpts=NULL,maxy=100)

#Reconstruct IPD
est_radio <- getIPD(prep=pre_radio,armID=0,tot.events=NULL)

# shift the IPD data into the proper format for 'FitDat()'
ipd <- est_radio$IPD
dat3 <- as.data.frame(cbind(rep(0, nrow(ipd)),ipd$time, ipd$status))
colnames(dat3) <- c("Entry", "Time", "Cens")

# use FitDat function to fit the historical dat
modelSelect <- FitDat(dat3)
modelSelect$AIC
# Weibull
# 301.7776

# check the estimated parameters from the modeling results
modelSelect$parameter.estimates
# $Weibull
# shape     scale
# 0.1133671 3.9939753