{
  "$schema": "https://terraevidence.com/evidence-record.schema.json",
  "recordId": "EP-PUB-009",
  "version": "1.0",
  "status": {
    "code": "reviewed-for-stated-scope",
    "label": "Reviewed for stated scope",
    "meaning": "Checked for the stated wording, sources, methods, context, limits, and review period; not universally proven."
  },
  "topic": "Indicator validity",
  "title": "An indicator is not automatically the outcome it represents.",
  "claim": "A measured indicator can provide useful evidence about a defined soil property, process, or function, but a change in that indicator should not be presented as proof of a different or broader outcome unless the relationship has been shown to be reliable for the intended purpose and context.",
  "summary": "Indicators make difficult properties or processes observable, but their meaning depends on what was measured, how it was measured, the function or outcome of interest, and the context of use. Analytical accuracy, correlation, or biological plausibility does not by itself establish that an indicator can substitute for a final outcome.",
  "evidenceSupports": [
    "Define the outcome or function of interest before selecting an indicator. Preserve the indicator's measurement method, context, timing, scale, uncertainty, and intended use. Test whether it is sensitive to the relevant change and whether its relationship with the outcome is reliable in the soils, climates, crops, management systems, and decisions where it will be used."
  ],
  "doesNotEstablish": [
    "A change in soil respiration, microbial biomass, enzyme activity, nutrient concentration, organic matter, plant color, or another intermediate measure does not by itself establish improved soil health, crop performance, resilience, environmental benefit, or decision value. Correlation, biological plausibility, or analytical accuracy alone does not validate an indicator as a substitute for a different final outcome."
  ],
  "sources": [
    {
      "sourceId": "EP-PUB-009-S1",
      "sourceType": "institutional-guidance",
      "institution": "United States Department of Agriculture Natural Resources Conservation Service",
      "title": "Soil Health Assessment",
      "url": "https://www.nrcs.usda.gov/conservation-basics/soil/soil-health/soil-health-assessment",
      "relevance": "Explains that soil health is not measured directly, that indicators provide clues about soil functions, and that useful indicators should relate to changes in those functions and be interpreted through patterns and comparisons."
    },
    {
      "sourceId": "EP-PUB-009-S2",
      "sourceType": "institutional-guidance",
      "institution": "United States Environmental Protection Agency",
      "title": "Assessment Endpoints",
      "url": "https://www.epa.gov/n-steps-online/assessment-endpoints",
      "relevance": "Describes endpoints as measurable expressions linked to ecological conditions and management goals, with relevance, sensitivity, measurability, and adequate data among the characteristics needed for their use."
    },
    {
      "sourceId": "EP-PUB-009-S3",
      "sourceType": "institutional-guidance",
      "institution": "FDA-NIH Biomarker Working Group",
      "title": "Validation",
      "url": "https://www.ncbi.nlm.nih.gov/books/NBK464453/",
      "relevance": "Distinguishes analytical validation from showing that a measure reflects or predicts the relevant concept, and explains that validation is tied to a specified purpose and context of use."
    }
  ],
  "scope": {
    "reviewedPeriod": "2026-08",
    "applicability": [
      "Evaluating claims that use soil, plant, biological, chemical, visual, or intermediate measurements as indicators of a broader function or outcome."
    ],
    "limitations": [
      "Does not rank particular soil indicators or establish universal thresholds; indicator performance depends on the defined function, method, setting, timing, scale, and decision.",
      "The FDA-NIH source supplies a general fit-for-purpose validation principle from biomarker science; it is not direct evidence that any soil or plant indicator is valid for a particular agricultural outcome.",
      "Does not imply that indirect indicators are unhelpful, and does not provide personalized fertilizer, lime, amendment, crop, environmental, pest-control, or safety recommendations."
    ],
    "openQuestion": "Which affordable soil and plant indicators reliably predict defined garden outcomes, for which decisions and settings, and with what error rates?"
  },
  "useBoundary": "This reviewed record supports careful interpretation of indicators and intermediate measurements. It does not validate a particular test, score, product claim, threshold, or proxy for a different outcome; establish improved soil health, crop performance, resilience, or environmental benefit from one indicator change; or provide personalized fertilizer, lime, amendment, crop, environmental, pest-control, or safety recommendations. Preserve the measured indicator separately from the outcome it is intended to inform and seek fit-for-purpose validation or qualified guidance when a consequential decision requires it.",
  "humanReadableUrl": "https://terraevidence.com/earth-project-reviewed-foundations#ep-pub-009",
  "machineReadableUrl": "https://terraevidence.com/evidence-records/ep-pub-009.json",
  "revision": {
    "version": "1.0",
    "publishedDate": "2026-08-17",
    "lastReviewedPeriod": "2026-08"
  }
}