SM {HCTDesign}R Documentation

Sample size in terms of number of subjects in the experimental group

Description

Calculates the total number of subjects for the experimental group using the total number of events(d2max:the output from design functions) and the estimated failure probability based on the person level historical control data and proportional hazard assumption.

Usage

SM(time, event, d2max, opt = "KM", event_ind, ta, tf, delta)

Arguments

time

event time vector from person level historical control data.

event

numeric vector indicating the status of event from person level historical control data.

d2max

maximum number of events in the experimental group calculated from the design function.

opt

the method of fitting survival curve-"log_normal" or "KM" (log-normal or Kaplan Meier). Default is "KM".

event_ind

numeric value indicating the occurrence of event.

ta

enrollment time.

tf

follow-up time.

delta

hazard ratio.

Value

Returns the value of sample size.

Author(s)

Tushar Patni, Yimei Li, Jianrong Wu, and Arzu Onar-Thomas.

References

Wu J, Xiong X (2016). “Survival trial design and monitoring using historical controls.” Pharmaceutical Statistics, 15(5), 405-411.

Wu J, Li Y (2020). “Group sequential design for historical control trials using error spending functions.” Journal of Biopharmaceutical Statistics, 30(2), 351-363.

Examples

time<-c(20,65,12,50,58,65,45,44)
event<-c(1,0,0,0,1,1,1,1)
d2max=57
gg<-SM(time,event,d2max,opt="log_normal",ta=4,tf=3,delta=0.57,event_ind=1)

[Package HCTDesign version 0.7.2 Index]