Thursday Full-Day Workshops

8. Dose-response modeling-benchmark dose modeling approaches using online and desktop versions of EPA’s Benchmark Dose Software (BMDS) and NIEHS’ ToxicR

Speaker: J Allen Davis

Description: In 2022, EPA released BMDS Online (, a browser-based version of BMDS to allow users to run BMDS on any computer with access to the internet.  Recently, EPA has released BMDS Desktop (a Python-based graphic user interface) to replace the Excel-based BMDS 3.3.  Additionally, NIEHS has further expanded dose-response capabilities through the release of the R-based ToxicR Bayesian modeling platform that “untethers” BMDS and other models from standard parameterizations, expanding its capabilities for research applications.

This workshop will cover dose-response analyses (frequentist and Bayesian); participants will learn and practice (through demos and hands-on exercises) dose-response modeling of dichotomous, continuous, cancer, and developmental toxicity response data using BMDS Online and BMDS Desktop.  Following these introductory analyses, participants will learn and practice the use of Bayesian models, including the application of a Bayesian framework for model averaging using ToxicR.  Participants will explore model averaging approaches for dichotomous and continuous data, including new model averaging capabilities for continuous data that include the European Food Safety Authority’s (EFSA) suite of continuous models currently only available in ToxicR. The research functionality and modeling capacity of the ToxicR platform will be demonstrated. Hands-on exercises in ToxicR will be provided.  Participants will be shown how to modify prior assumptions and perform sensitivity analyses to investigate the default prior’s effect on a given analysis.  Additional features of the package that allow for scripted batch processing, advanced graphics, and custom BMD analysis will also be highlighted.