Bayesian Design of Non-Inferiority Clinical Trials via the Bayes Factor

Abstract

We developed a Bayes factor based approach for the design of non-inferiority clinical trials with a focus on controlling type I error and power. Historical data are incorporated in the Bayesian design via the power prior discussed in Ibrahim and Chen (2000). The properties of the proposed method are examined in detail. An efficient simulation-based computational algorithm is developed to calculate the Bayes factor, type I error and power. The proposed methodology is applied to the design of a non-inferiority medical device clinical trial.

Keywords: Fitting prior; Power prior; Sample size determination; Sampling prior; Type I error.

Figure 1

The plot of the power as a function of θ₁ under θ₀ = 1, σ = 1.5, μ = 1, τ = 1.5, δ = 1, and n = 15

Figure 2

Type I error and power versus a₀ under p_0c=(0.08, 0.092), $p_{0c}^{(B_0)}=0.08$, n_t = 900, and n_c = 300

Figure 3

Type I error and power versus total sample size n under p_0c = (0.08, 0.092), $p_{0c}^{(B_0)}=0.08$, a₀ = 1, and n_t/n_c = 3