Specification Guidance

How This Guide is Organized

The Home page includes a Table of Contents listing all components of this Implementation Guide (IG) and provides an overview of its structure and intended use.

In addition to this section, the Business Context page provides context on the artifacts included in this IG, their purpose, and how they fit within broader interoperability efforts.

How to Use This Specification

CA Core+ serves as a foundational building block for:

• Jurisdictional implementation guides
• Cross-provincial data exchange initiatives
• Pan-Canadian interoperability efforts

It provides a set of reusable, standardized FHIR artifacts that jurisdictions, EHR vendors, and implementers can leverage to support consistent health data exchange.

Each Module (e.g., Common Data Exchange Profiles, Workflows, Consent Management) is a reusable set of FHIR profiles and extensions designed around shared, recurring patterns. The modular approach enables flexibility while maintaining alignment with pan-Canadian goals.

Note: CA Core+ is not intended for standalone implementation. Instead, it provides a harmonized, interoperable foundation that downstream guides are expected to build upon.

Understanding Modules and Reuse

Modules in CA Core+ are organized by shared functional capabilities such as workflow orchestration and consent capture. The profiles within these modules are:

• Designed for referencing or slicing, not for redefinition
• Aligned with pan-Canadian standards such as CACDI where applicable
• Structured for downstream customization, allowing implementers to add Must Support flags, refine cardinality, or apply jurisdictional value sets

Interoperability Best Practices

To maintain interoperability:

• Avoid duplicating profiles already defined in CA Core+
• If additional constraints are required, derive from existing profiles rather than redefining them
• Use standardized extensions and terminology bindings to ensure semantic consistency across implementations

More recommendations on deriving from CA Core+ can be found on the General Guidance page.

Jurisdictional Adaptation Guidance

Jurisdictions adopting CA Core+ are encouraged to:

• Reuse existing profiles and extensions wherever possible
• Define additional constraints, Must Support flags, or value sets via derived profiles
• Avoid redefining core entities like Patient, Practitioner, or Organization unless essential
• Document all jurisdiction-specific adaptations, such as invariants or logic added to base artifacts

If a required concept is missing, new extensions or terminology bindings can be proposed through the Specification Feedback process.

Versioning and Update Expectations

CA Core+ follows HL7 FHIR Implementation Guide versioning conventions:

• Patch versions (e.g., 1.1 → 1.1.1): Bug fixes and clarifications; no content changes
• Minor versions (e.g., 1.1 → 1.2): Backward-compatible refinements and additions
• Major versions (e.g., 1.x → 2.0): Breaking changes or significant restructuring

Version announcements will appear on the Home page and other stakeholder channels. A defined release cycle will be established in alignment with the PCHDCF.

Readers are encouraged to track updates in the Change Log section.

Conformance and Certification

At this time, CA Core+ is not associated with a national certification program or formal test suite. However:

• Profiles are structured to support future interoperability testing and validation
• Downstream implementation guides MAY define their own conformance rules using CA Core+ artifacts
• Jurisdictions reusing CA Core+ MAY establish localized conformance expectations for their specific use cases

Future versions of CA Core+ may include formalized conformance requirements aligned with pan-Canadian interoperability initiatives.