The Impact of Using Informative Priors in a Bayesian Cost-Effectiveness Analysis: An Application of Endovascular versus Open Surgical Repair for Abdominal Aortic Aneurysms in High-Risk Patients

Background. Bayesian methods have been proposed as a way of synthesizing all available evidence to inform deci-sion making. However, few practical applications of the use of Bayesian methods for combining patient-level data (i.e., trial) with additional evidence (e.g., literature) exist in the cost-effectiveness literature. The objective of this study was to compare a Bayesian cost-effectiveness analysis using informative priors to a standard non-Bayesian nonparamet-ric method to assess the impact of incorporating additional information into a cost-effectiveness analysis. Methods. Patient-level data from a previously published nonrandom-ized study were analyzed using traditional nonparametric bootstrap techniques and bivariate normal Bayesian models with vague and informative priors. Two different types of informative priors were considered to reflect different valu