Addressing prior-data conflict with empirical meta-analytic-predictive priors in clinical studies with historical information.

A common question in clinical studies is how to use historical data from earlier studies, leveraging relevant information into the design and analysis of a new study. Bayesian approaches are particularly well-suited to this task, with their natural ability to borrow strength across data sources. In this paper, we propose an eMAP approach for incorporating historical data into the analysis of clinical studies, and we discuss an application of this method to the analysis of observational safety studies for a class of products for patients with hemophilia A. The eMAP prior approach is flexible and robust to prior-data conflict. We conducted simulations to compare the frequentist operating characteristics of three approaches under different prior-data conflict assumptions and sample size scenarios.