2018 External Review of Bayesian Models and Model Averaging Software
In 2018, the BMDS Bayesian models and Bayesian model averaging (BMA) software package for performing dose-response analyses of dichotomous data was externally reviewed by three experts in Bayesian risk assessment methods and dose-response modeling. Peer review comments are documented in a Bayesian Model Averaging for Dichotomous Data Peer Review Report.
The primary purpose of this review was to obtain external expert opinions on EPA’s proposed model averaging approach for the derivation of BMDBMDAn exposure due to a dose of a substance associated with a specified low incidence of risk, generally in the range of 1% to 10%, of a health effect; or the dose associated with a specified measure or change of a biological effect. and BMDLBMDLA lower one-sided confidence limit on the BMD. values from dichotomous dose-response datasets. Reviewers were asked to read the review documents describing EPA's proposed BMA method and respond to several specific charge questions relating to the proposed method that are documented in the Peer Review Report.
The reviewers generally agreed that the BMA software package produced statistically valid results. They praised the innovative approaches with comments such as “substantive models going into model averaging are very well thought out,” “highly valuable,” and “…heavily encourage the Agency to adopt the kinds of methods proposed here into its next version of BMDS.”
Several recommendations were made regarding enhancements that could facilitate or expand its practical application, and how the documentation and outputs could be improved with respect to clarity.
EPA revised the BMA software package and documentation in response to these comments, incorporating most of the suggested revisions. The BMDS User Guide for BMDS v3.0 and higher contains details necessary to understand the program's assumptions and application.
- Model Averaging Webinar Workshop Announcement
- Model Averaging Webinar Workshop Support Materials
- Model Averaging Workshop - Final Report