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  2. Causal Analysis/Diagnosis Decision Information System (CADDIS)

Learn About Responses

What Are Responses?

Responses are the biological results of exposure to proximate stressors.

  • Beyond this page, there is currently no response module in CADDIS.

How Do Responses Relate to Candidate Causes?

A candidate cause is a hypothesized cause of a specific environmental impairment, sufficiently credible to be analyzed in a causal assessment.

A candidate cause can be simply a proximate stressor (e.g., low dissolved oxygen concentration), that is, the stressor that is directly responsible for the observed biological response.

However, a candidate cause also may include more detailed information about the causal pathway, such as the mechanism or organismal level response that resulted in the ultimate response of interest (e.g., fish died due to asphyxiation). Including more detail may help identify ways to distinguish among different candidate causes included in the assessment.

  • Learn more about candidate causes under Tips for Listing Candidate Causes.

Causal Analysis/Diagnosis Decision Information System (CADDIS)

  • CADDIS Home
    • About CADDIS
    • Frequent Questions
    • Publications
    • Recent Additions
    • Related Links
    • CADDIS Glossary
  • Volume 1: Stressor Identification
    • About Causal Assessment
    • Getting Started
    • Step 1. Define the Case
    • Step 2. List Candidate Causes
    • Step 3. Evaluate Data from the Case
    • Step 4. Evaluate Data from Elsewhere
    • Step 5. Identify Probable Causes
  • Volume 2: Sources, Stressors and Responses
    • About Sources
      • Urbanization
    • About Stressors
  • Volume 3: Examples and Applications
    • Analytical Examples
    • Worksheet Examples
    • State Examples
    • Case Studies
    • Galleries
  • Volume 4: Data Analysis
    • Selecting an Analysis Approach
    • Getting Started
    • Basic Principles & Issues
    • Exploratory Data Analysis
    • Basic Analyses
    • Advanced Analyses
    • PECBO Appendix
    • Download Software
    • Data Analysis Topics (A -Z)
  • Volume 5: Causal Databases
    • Learn about CADLink
Contact Us about CADDIS
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 7, 2025
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