A committee of the National Academies of Sciences (NAS) hosted a workshop to discuss evidence integration, which is the summary step of the systematic review process conducted by the US Environmental Protection Agency (EPA) Office of Research and Development.

Topic areas include: 

• Lessons Learned from Recent International Workshops on Evidence integration in Risk Assessment,
• Best Practices in Evidence Integration,
• Approaches for Using Mechanistic Data to Integrate Evidence from Animal and Human Studies: General Considerations,
• Systematic Review-Enabled Evidence Integration: Case Studies, and
• Practical Approaches to Expedited Evidence Integration.

During evidence integration, also referred to as weight-of-evidence evaluation, conclusions are drawn from each line of evidence that is relevant to the predefined PECO criteria.  Evidence integration generally involves subjecting the relevant evidence to a causal analysis,  which can be conducted using both qualitative and quantitative approaches.

PECO refers to population, exposure, comparators, and outcomes.

This is a structured process by which conclusions are drawn regarding the potential health effects in exposed humans, incorporating judgments about the strength of the human and animal evidence (both within and across lines of evidence) as well as information from mechanistic data necessary to answer key questions. 

The objective of the workshop was to explore relevant strategies for addressing challenges that arise for EPA during evidence integration in chemical assessments, with a primary focus on the use of mechanistic data. Poster sessions accompanied the workshop in order to address topics that are relevant to the workshop session topics.

• Download the presentation, workshop video and booklet at, Evidence Integration in Chemical Assessments Workshop Exit
• View the posters and presentations (NAS Website) at Evidence Integration in Chemical Assessments Workshop Materials Exit
• NAS Workshop Agenda (Jun 3-4, 2019) Exit

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Download the EPA Posters

• Evaluating the consistency of heterogeneous results: important determinants of inconsistency (PDF)(1 pg, 934 K, 2019-06-03)
• Evidence Integration in Integrated Science Assessments (ISAs): A Case Study from the Draft Particulate Matter ISA (PDF)(1 pg, 467 K, 2019-06-03)
• Evidence Synthesis and Integration in the IRIS Program (PDF)(1 pg, 855 K, 2019-06-03)
• Modeling mechanistic processes from source to outcome to support evidence integration and inform risk assessment (PDF)(1 pg, 882 K, 2019-06-03)
• Role of Semantics, Ontologies, and Adverse Outcome Pathways as a Point of Integration in Chemical Assessments (PDF)(1 pg, 325 K, 2019-06-03)
• Targeted Mechanistic Evidence Synthesis to Inform Evidence Integration Decisions on the Potential Human Carcinogenicity of Naphthalene Exposure (PDF)(1 pg, 222 K, 2019-06-03)
• Technological Tools for Evidence Integration (PDF)(1 pg, 531 K, 2019-06-03)
• Using In vitro ToxCast Assays to Evaluate Mechanistic Plausibility and Build Confidence in the Selection of Analogues for Quantitative Read-Across: A Case Study on p,p’-Dichlorodiphenyldichloroethane (PDF)(1 pg, 1 MB, 2019-06-03)
• Using study evaluation to inform evidence integration: Application in a systematic review of hexavalent chromium male reproductive outcomes (PDF)(1 pg, 681 K, 2019-06-03)