Predictive probability of "Declare efficacy" at final analysis
Usage
pred_prob2(nmax, n1, m, pt, theta0, a = 1, b = 1)
Arguments
- nmax
number of subjects at final analysis
- n1
number of subjects at current stage
- m
number of responders at current stage
- pt
posterior probability target to declare efficacy at final analysis
- theta0
efficacy boundary of ORR
- a, b
parameters of prior beta distribution
Value
the predictive probability
Details
Declare efficacy at final analysis if the posterior probability at FA satisfies:
$$posterior\_probability(\theta > theta0) > pt$$
And the predictive probability is the expectation of final success(declare efficacy),
based on current results.