What is PROcEED?

PROcEED is a Web-based application used to perform probabilistic reverse dosimetry calculations for estimating a distribution of exposure concentrations likely to have produced biomarker concentrations measured in a population. PROcEED transforms the distribution of measured biomarker concentrations to a potential distribution of unmeasured exposure concentrations using one of two approaches: (1) the Discretized Bayesian Approach, or (2) the Exposure Conversion Factor Approach. The second approach is suitable only in cases where the exposure-biomarker relationship is linear.

What are the benefits of using PROcEED?

PROcEED is free and does not require a license to use. The software uses a Web-based graphical user interface enabling users to upload the necessary input files and display the results of reverse dosimentry calculations.

Who should use PROcEED?

Users should be familiar with the concepts and terminology of pharmacokinetic modeling, tissue dosimetry, the Monte Carlo method and Bayesian statistics.

How does PROcEED work?

PROcEED uses statistical methods to transform the distribution of measured biomarker concentrations to a potential distribution of unmeasured exposure concentrations. This transformation allows scientists to study the causes of exposure. Users can opt for either graphical representation of results or export them to a text file.

PROcEED requires, as inputs, (1) predicted biomarker concentrations from a Monte Carlo simulation of a pharmacokinetic model and (2) a vector of measured biomarker concentrations.
The tool accepts a variety of text-based file formats outlined in the help documentation and described through the web-interface. PROcEED then performs reverse dosimetry calculations using either the Descretized Bayesian Approach or the Exposure Conversion Factor Approach to provide both graphical probability distributions as well as exportable results.

PROcEED User Information:

• PROcEED Installation and Quickstart
• PROcEED.war - Web application archive(13 MB)
• Example.zip - Files for testing the installation

Technical Contact:

• Cecilia Tan, Ph.D. (tan.cecilia@epa.gov)