optimal_OneStage {BayesDesign} | R Documentation |
Obtain design settings for one-stage Bayesian Single-Arm Phase II Trial with Time-to-Event Endpoints
Description
Obtain design parameters, type I error, power and operating characteristics of the Bayesian Single-Arm Phase II Trial Designs with Time-to-Event Endpoints (Wu et al. 2021). The exponential distribution is assumed for the survival time. The gamma prior is used here
Usage
optimal_OneStage(alphacutoff, powercutoff, S0,
x, ta, tf, a = 2, delta, ntrial,
complete = "partial", seed = 8232)
Arguments
alphacutoff |
the desired type I error to be controlled |
powercutoff |
the desired power to be achieved |
S0 |
the survival probability at timepoint x |
x |
the survival probability S0 at timepoint x |
ta |
accrual duration |
tf |
follow-up duration |
a |
shape parameter of prior distribution. The default value is a = 2 |
delta |
hazard ratio |
ntrial |
the number of simulated trials |
complete |
whether output the full or partial information. The default value is complete = "partial". If want to show full results, it would be complete = "complete" |
seed |
the seed. The default value is seed = 8232 |
Value
optimal_OneStage()
depending on the argument "complete", it returns a vector of partial information/complete information which includes:
partial information: (1) m: number of events of the whole design (2) n: number of patients of the whole design (3) k: total observation time of the whole design (4) typeI: type I error of the whole design (5) power: power of the whole design (6) ES1: expected sample size under alternative hypothesis (7) ES0: expected sample size under null hypothesis
full information: (1) eta: cutoff point of "Go" at final stage of analysis (2) zeta: cutoff point of "no-Go" at final stage of analysis (3) m: number of events of the whole design (4) n: number of patients of the whole design (5) k: total observation time of the whole design (6) typeI: type I error of the whole design (7) power: power of the whole design (8) ES1: expected sample size under alternative hypothesis (9) ES0: expected sample size under null hypothesis
Author(s)
Chia-Wei Hsu, Haitao Pan, Jianrong Wu
References
Jianrong Wu, Haitao Pan, Chia-Wei Hsu (2021). "Bayesian Single-Arm Phase II Trial Designs with Time-to-Event Endpoints." Pharmaceutical Statistics. Accepted
Examples
### Design 1
# H0 vs. H1: 17% vs. 40% (4-month PFS)
# that is, S0 = 0.17, and hazard ratio, e.g., delta = 0.517
# x = 4
optimal_OneStage(alphacutoff = 0.1, powercutoff = 0.8,
S0 = 0.17, x = 4, ta = 6, tf = 6,
delta = 0.517, ntrial = 10)
### Design 2
# H0 vs. H1: 17% vs. 30% (4-month PFS)
# that is, S0 = 0.17, and hazard ratio, e.g., delta = 0.679
# x = 4
optimal_OneStage(alphacutoff = 0.1, powercutoff = 0.8,
S0 = 0.17, x = 4, ta = 6, tf = 6,
delta = 0.679, ntrial = 10)