Relationship to Other Specifications

The CA Core+ Implementation Guide exists within a broader ecosystem of specifications that enable interoperability in the pan-Canadian context. These include content frameworks, profiling conventions, FHIR interaction models, and jurisdictional implementation guides. Together, these layers support pan-Canadian consistency while allowing flexibility for jurisdiction-specific requirements.

CA Core+ was developed in alignment with this ecosystem, drawing upon foundational resources and extensive stakeholder input.

Alignment with the Pan-Canadian Health Data Content Framework (PCHDCF)

The Pan-Canadian Health Data Content Framework (PCHDCF) provides a conceptual and semantic foundation for defining interoperable health data across Canada. It outlines data domains, concepts, and relationships critical for both clinical and administrative exchange.

CA Core+ operationalizes the PCHDCF by translating these domains into modular, reusable FHIR profiles and implementation artifacts that:

• Provide foundational FHIR representations of key health data concepts
• Ensure consistent structure, terminology, and constraints across implementation guides
• Enable jurisdictional and domain-specific guides to derive from or extend pan-Canadian building blocks

In this way, CA Core+ acts as the technical instantiation of the PCHDCF—bridging conceptual frameworks with real-world implementations. As the PCHDCF evolves, CA Core+ will adapt alongside it to reflect new domains, refined concepts, and emerging priorities.

Canadian FHIR Baseline

The Canadian FHIR Baseline is a community-driven initiative defining shared profiling conventions, extensions, and terminology bindings across Canadian FHIR implementation guides.

This work reflects broad collaboration across jurisdictions and organizations, and has contributed meaningfully to the advancement of interoperability in Canada.

As part of the CA Core+ harmonization initiative, an evaluation is underway to identify how these efforts can align and reinforce one another — ensuring consistency with pan-Canadian frameworks such as the Logical Data Model (LDM). Canada Health Infoway is actively exploring how to leverage complementary capabilities across initiatives while continuing to deliver on its Interoperability Roadmap.

CA:FeX – Canadian FHIR Exchange

The CA:FeX specification defines interaction patterns, search parameters, and read capabilities for FHIR servers in Canada.

• CA Core+ defines what data should look like—i.e., structure, cardinality, terminology
• CA:FeX defines how that data is exchanged—i.e., RESTful behavior and conformance expectations

This separation allows implementers to test and certify against each independently. For example, CA Core+ artifacts can be referenced in CapabilityStatement.instantiates while FHIR endpoints conform to CA:FeX interaction rules.

Domain-Specific Implementation Guides

Domain-specific implementation guides define additional constraints for specific use cases, such as:

• Pan-Canadian Patient Summary(PS-CA)
• Pan-Canadian eReferral-eConsult (CA:eReC)
• Pan-Canadian Care Service Directory (CA:CSD)

These guides are expected to:

• Reference or derive from CA Core+ profiles
• Reuse modules such as Workflows, Common Data Exchange, and Consent
• Apply further constraints (e.g., MustSupport, cardinality) only when required

Example: Patient.birthDate is optional in CA Core+ 1.0.0 to support scenarios where a birth date is unknown. However, in PS-CA, it may be constrained to 1..1 with MustSupport for summary exchange.

Future domain-specific guides are expected to build directly on CA Core+ artifacts and conventions as a best practice.

Jurisdictional Implementation Guides

Jurisdictional Implementation Guides (IGs) are developed by provinces, territories, or health regions to reflect local policies, priorities, and timelines. These IGs:

• May be based on or extend domain-specific guides
• Are expected to align with CA Core+ as closely as possible
• Should reuse and constrain CA Core+ profiles rather than redefine them

CA Core+ supports jurisdictions by:

• Offering a consistent set of reusable modules and baseline profiles
• Supporting extensibility where local requirements differ
• Promoting alignment with pan-Canadian frameworks like the Relationship to PCHDCF and PCHDCF

To maintain interoperability, jurisdictions are encouraged to:

• Reference or constrain CA Core+ profiles
• Reuse modules such as Common Data Exchange, Workflows, and Consent
• Limit deviations unless required by local context
• Participate in shared governance and feedback cycles via the Specification Feedback process

Looking Ahead

CA Core+ will continue to expand—adding new modules, profiles, and supporting artifacts in response to pan-Canadian and jurisdictional priorities. The long-term goal is convergence: a harmonized set of FHIR artifacts that reflect pan-Canadian goals and real-world implementation needs.

By working collaboratively through shared tools like CA Core+, Canadian stakeholders can:

• Reduce duplication of effort
• Promote semantic and technical interoperability
• Accelerate delivery of high-quality digital health solutions