Profiling Conventions & Approach

pCHDCF Translation Practices

This section will continue to expand in future iterations as content is further developed in the pan-Canadian Health Data Content Framework (pCHDCF). This version focuses on 1) mapping the data element definitions from the pCHDCF CACDI, 2) outlining a potential logic for translating initial expectations into FHIR profiles, 3) initial introduction of terminology for select concepts.

Mappings to the Data Content Standard data elements are defined in-line within the profiles and can be found on each profile's page.

Translating Obligations

In line with General Principles & Design these profiles make use of an emerging a new (and evolving) mechanism in FHIR that provides a consistent and machine processable way for profiles to define their expectations for system behaviors. This mechanism is the Obligation Extension which is defined in the cross-version extension registry but has been recently expanded to support application. The updated definition can be found in the CI Build FHIR Extension Registry definition.

Note: The CACDI (Canadian Core Data for Interoperability) has recently been announced as a new artefact in the pCHDCF that will define the standardized set of essential health data elements and associated value sets within the context of a common architecture. The CA Core+ will package the CACDI into a set of core FHIR profiles to support interoperability and data exchange.

The CACDI is early in its maturity requirement strengths (e.g., essential, recommended, no-absent, allow-absent) but the differentiation between essential and recommended elements has been used to identify which elements will carry Obligation expectations in early releases of CA Core. Expectations on whether the element in CACDI is allowed to be absent or not are expected to drive cardinality expectations in early releases of the CA Core.

These definitions and the approach in the CACDI towards applying these requirements may continue to evolve.

In the meantime, the requirement strengths above have been translated to the following obligation codes:

CACDI Strength	Target for Expectation	Obligation Code
Essential	Resource Producer	SHALL:able-to-populate
Essential	Resource Consumer	SHALL:handle
Recommended	Resource Producer	No Obligation Applied in Current Version
Recommended	Resource Consumer	No Obligation Applied in Current Version

Additional considerations:

• Some expectations are expected to be nested/conditional; others will require the backbone element carries the same strength
• Recommended elements identified may not carry the SHALL:able-to-populate obligation. These will be socialized with a comment until further is known about expectations for consumers/producers.