stopbound_pred {ph2bayes} | R Documentation |
The stopping boundaries based on Lee and Liu's criterion.
stopbound_pred(theta, type, nmax, alpha_e, beta_e, p_s, theta_t)
theta |
the cutoff probability: typically, θ = [0.95, 0.99] for superiority, θ = [0.01, 0.05] for futility. |
type |
type of boundaries: "superiority" or "futility". |
nmax |
the maximum number of patients treated by the experimental drug. |
alpha_e |
the hyperparameter (shape1) of the Beta prior for the experimental drug. |
beta_e |
the hyperparameter (shape2) of the Beta prior for the experimental drug. |
p_s |
the the response rate for the standard drug. |
theta_t |
the prespecified target probability; tipically, θ_T = [0.85, 0.95]. |
boundset |
the boundaries set: U_n or L_n |
Lee, J. J., Liu, D. D. (2008). A predictive probability design for phase II cancer clinical trials. Clinical Trials 5: 93-106.
Yin, G. (2012). Clinical Trial Design: Bayesian and Frequentist Adaptive Methods. New York: Wiley.
stopbound_pred(0.05, "futility", 40, 0.6, 1.4, 0.3, 0.85) stopbound_pred(0.05, "futility", 30, 0.4, 1.6, 0.2, 0.85) stopbound_pred(0.95, "superiority", 40, 0.6, 1.4, 0.3, 0.85)