A Bayesian Meta-analysis Method for Estimating Risk Difference of Rare Events

ABSTRACT

Bayesian meta-analysis has been more frequently utilized for synthesizing safety and efficacy information to support landmark decision-making due to its flexibility of incorporating prior information and availability of computing software. However, when the outcome is binary and the events are rare, where event counts can be zero, conventional meta-analysis methods including Bayesian methods may not work well. Several methods have been proposed to tackle this issue but the prior knowledge of event rate was not utilized to increase precision of risk difference estimates. To better estimate risk differences, we propose a new Bayesian method, Beta prior BInomial model for Risk Differences (B-BIRD), which takes into account the prior information of rare events. B-BIRD is illustrated using a real data set of 48 clinical trials about a type 2 diabetes drug. In simulation studies, it performs well in low event rate settings.

KEYWORDS:

• Bayesian
• meta-analysis
• rare event
• risk difference

Acknowledgement

The research was sponsored by AbbVie. AbbVie contributed to writing, reviewing and approving the publication. Yao Yu is an employee of AbbVie, Inc. Yuanyuan Tang, Qi Tang, and Shihua Wen are former employees of AbbVie. Yuanyuan Tang is currently employed by Saint Luke’s Health System in Kansas City, Missouri; Qi Tang is currently employed by Sanofi, and Shihua Wen is currently employed by Novartis Pharmaceuticals. The authors thank Dr. Alan Hartford and the reviewers for their helpful comments and suggestions leading to a much improved version of the article.