Result Normalization

Lab Network returns laboratory results as FHIR R4 resources for consistent downstream retrieval and use.

Normalization supports clinical workflows, analytics, and interoperability by representing results in standardized FHIR structures while preserving traceability to the source laboratory and originating order where available.

Overview

Laboratory partners may return results in different formats and levels of detail.

Lab Network represents returned results using FHIR R4 resources so you can:

• Retrieve structured results consistently across laboratories
• Associate results with the originating order
• Access document-based artifacts when provided
• Preserve traceability for reconciliation and audit workflows

Normalization supports both structured and document-based results.

Supported Result Types

Lab Network may return:

• Structured results as DiagnosticReport and Observation
• Document-based results as DocumentReference
• Downloadable file content as Binary
• Traceability through FHIR relationships, identifiers, and Provenance resources where available

A single order may return:

• Structured results only
• Document-based results only
• Both structured and document-based results

Resource Mapping

Lab Network uses the following FHIR R4 resources to represent normalized results:

These resources are linked to preserve order context and support downstream processing.

Standardization

Normalized results use standard FHIR structures to support consistent retrieval and interpretation.

Where supported by the source data and workflow, normalized content may include standard coding systems such as:

• LOINC for test codes
• SNOMED CT for selected clinical concepts and interpretations
• UCUM for units of measure

Source-specific identifiers and metadata may also be preserved when needed for traceability.

Normalization standardizes structure, not content. Result availability, coding, and level of detail depend on the performing laboratory.

Result Relationships

Lab Network maintains FHIR relationships between orders and results to support reconciliation and workflow tracking.

Common relationships include:

• DiagnosticReport.basedOn: references the originating RequestGroup
• DiagnosticReport.result: references associated Observation resources
• Observation.basedOn: references the originating RequestGroup
• DocumentReference.subject: references the patient associated with the result document

These relationships allow you to:

• Link structured results to the original order
• Reconstruct the order-to-result workflow
• Track fulfillment status across returned resources
• Reconcile document-based and structured results when both are present

Structured Results

Structured results are returned through:

• DiagnosticReport: overall report context
• Observation: discrete analyte or result values

Use structured results when you need:

• Downstream clinical ingestion
• Analytics and reporting
• Discrete result processing
• Standardized result retrieval across laboratories

Example Structured Result

{
  "resourceType": "DiagnosticReport",
  "status": "final",
  "subject": {
    "reference": "Patient/12345"
  },
  "result": [
    {
      "reference": "Observation/obs1"
    }
  ]
}

{
  "resourceType": "Observation",
  "status": "final",
  "code": {
    "text": "Hemoglobin"
  },
  "valueQuantity": {
    "value": 13.5,
    "unit": "g/dL"
  }
}

Document-Based Results

Some laboratory partners return result artifacts such as PDFs or images.

Lab Network represents these through:

• DocumentReference: metadata and linkage
• Binary: downloadable file content

Use document-based results when you need:

• Original report artifacts
• Human-readable result documents
• Access to files that supplement structured content

Retrieval Patterns

Use common FHIR search patterns to retrieve normalized results.

Retrieve Structured Results by Order

GET /fhir/R4/DiagnosticReport?based-on=RequestGroup/{order-id}
GET /fhir/R4/Observation?based-on=RequestGroup/{order-id}

Retrieve Document-Based Results by Patient

GET /fhir/R4/DocumentReference?subject=Patient/{patient-id}&category=laboratory

Retrieve File Content

GET /fhir/R4/Binary/{id}

Workflow Considerations

Use normalized results as part of your end-to-end workflow.

Recommended practices:

• Store the originating RequestGroup.id for result retrieval
• Use based-on relationships to reconcile structured results with orders
• Expect asynchronous result delivery after laboratory processing
• Expect structured and document-based results to arrive at different times when both are available
• Handle both structured and document-based results when applicable
• Preserve identifiers needed for downstream audit or reconciliation workflows

Limitations

Normalization improves consistency, but returned content still depends on what the performing laboratory provides.

Differences may include:

• Availability of structured versus document-based results
• Level of coding standardization
• Presence of supplemental metadata
• Availability of downloadable artifacts

Your system should handle variation in source result content while relying on the normalized FHIR resource model for retrieval.

Summary

Result normalization allows you to retrieve laboratory results through consistent FHIR R4 resources across connected laboratory partners.

Lab Network returns structured and document-based results using standard FHIR resource types and maintains the relationships needed to link those results back to the originating order where applicable.

Use normalized results to support downstream clinical workflows, analytics, reconciliation, and document retrieval.