60.1.1Multi-Repo Data Blend

The Data Blend feature leverages the Master Data Management (MDM) module to link patient records from multiple sources that are segregated into separate repositories using Enterprise Identifiers (EIDs). Once linked, Smile's FHIR Gateway provides a unified front door to these distributed patient records, enabling provider systems to retrieve a complete view of patient information during a data export — even if only a single identifier is listed in a FHIR Group resource — without querying multiple repositories directly. The Auto-Expansion feature of MDM ensures that all records linked via an EID are automatically included in the export.

60.1.1.1Key Concepts

• Primary Patient: The patient record stored in the payer’s own repository (primary repository). This is the main record used in a FHIR Group for data exports.
• Secondary Patient: Related patient records stored in other repositories that contain data collected from other payers. These records are linked to the primary patient to provide a complete view of the patient’s information.
• Patient Stub: A minimal representation of the primary patient created in secondary repositories to enable linking across repositories.
• Enterprise Identifier (EID): A unique identifier that connects primary and secondary patient records, ensuring all related records are recognized as belonging to the same individual.
• EID Auto‑Expansion: The mechanism by which, when enabled (via the MDM module), all patient records linked by an EID are automatically included in a query or export.

60.1.2Where Application Gateway Fits In

• Patient Identity Routing: When a query (e.g., Patient/$everything) is initiated via the Gateway using a Patient ID from Repo 1, the Gateway recognizes that this Patient ID is also present in Repo 2 due to replication.
• Dual-Repo Aggregation:
  • The Gateway executes federated searches against both Repo 1 and Repo 2.
  • Using the replicated Patient ID and MDM's EID linkage, it retrieves all resources associated with the member (e.g., Coverage, ExplanationOfBenefit, Condition, Encounter, MedicationRequest).
• Normalization & Response Assembly:
  • The Gateway merges and deduplicates the data (as needed) before constructing a single, FHIR-compliant response bundle.
  • Optionally, Gateway policies can be applied to redact sensitive data or enforce record provenance tagging.

60.1.3How to Enable Data Blend

For instructions on enabling the feature, see How to Enable Data Blend.