Project Background

The acceleration in the use of virtual care and digital health tools has created a new urgency to address several common barriers to effective digital health, including:

  • Siloed information and a lack of interoperability, including lack of semantic interoperability as many EMR systems do not encode clinical data elements, which will be a major gap when transitioning towards international vocabulary standards

  • Constrained values (value sets) that are challenging for clinicians, voiced by jurisdictions and vendors

  • Aging and disconnected digital health systems and infrastructures that cannot easily communicate with one another

  • Messaging solutions that are not integrated into provider systems or workflows and are not user-friendly

Virtualization of care has heightened the need for safe and efficient electronic communication, collaboration and sharing of information across the circle of care. The COVID-19 pandemic has accentuated the importance of interoperability.

In support of provinces and territories, Canada Health Infoway is facilitating a national collaborative effort to advance interoperability in two priority areas identified through extensive consultations:

  • Secure sharing of patient summaries across different solutions to support transitions of care and cross-jurisdictional patient flows
  • Secure messaging between solutions to enable safer and more efficient collaboration across the circle of care (e.g., provider to provider secure electronic communication)

Need for Modern Exchange Standards

CA:FeX endevaours primarily to provide early guidance to Canadian implementers for the purposes of conformance. It aims to be compatible with the International Patient Access (IPA) and IHE profiles where applicable and is anticipated that more broadly adopted international specifications will superseded CA:FeX.

In addition, CA:FeX Interoperability Specifications, Use Cases and Definitions can be found here.

Exchange patterns outlined in IHE profiles, like Mobile access to Health Documents (MHD) and Cross-Enterprise Document Sharing (XDS), were initially explored as part of the pan-Canadian Patient Summary (PS-CA) Interoperability Specification. However, early implementers were quick to identify the need to put forward and harmonize around modern RESTful API patterns for exchanging documents and other forms of patient data.

As part of this discovery, a market scan was performed to evaluate patterns used in existing RESTful-driven FHIR Implementations guides (e.g., US Core, IPA, PACIO, IPS, etc.). Learnings from this scan, and feedback from the Canadian implementer community ultimately led to the development of the initial instalment of the Canadian FHIR Exchange (CA:FeX) Specification.

A primary driver of this specification is to fill the gap that "FHIR-first" implementers are experiencing with existing document exchange standards like MHD and XDS. One of these particular challenges, is the need to balance efficacious and consistent search patterns against the additional effort incurred to supply supplementary metadata/resources (e.g., DocumentReference) that include more potent attributes to aid in targeted searches.

Clinical systems in US markets are more familiar with using MHD-like patterns to exchange C-CDAs using FHIR - largely due to the proliferation of XDS implementations in the US Market. Many organizations that had already invested in XDS infrastructure opted to support a FHIR façade for retrieving C-CDAs and utilized MHD (and related IHE profiles) as the mechanism for doing so. Naturally, these systems are considering how to retrofit their existing configurations to support search and retrieval of other types of documents in a similar manner.

Systems that serve non-US markets (or new solutions built entirely in FHIR for document exchange) may not have the same historical context to immediately catalyze investment of effort to supply additional resources for more desirable search behaviors. Recently, new operations have been developed that are more lightweight and may ease the burden of supporting these more potent search attributes. However, these patterns are evolving and their place in the Canadian market is yet to be fully evaluated.

Pan-Canadian FHIR Exchange (CA:FeX) Interoperability Specifications

CA:FeX v1.0.0 Trial Implementation

Given the focus of early implementers to exchange patient summaries as a FHIR Document, CA:FeX 1.0.0 Trial Implementation was scoped to outline simple exchange patterns that allow for the search, retrieval, and submission of FHIR Documents. There are multiple ways in which documents can be formatted and interacted with in the RESTful paradigm. To read more about the various ways in which documents may be formatted, see Document Exchange and the CA:FeX Whitepaper.

Details regarding CA:FeX v1.0.0 Trial Implementation and its earlier releases can be found here.

CA:FeX v2.0.0 DFT

This release expands on CA:FeX v1.0.0 Trial Implementation and provides additional guidance on the initial set of Search Parameters and resource exchange capabilities that FHIR Servers in Canada are expected to support. This release also explores an initial set of Operations that are expected to provide value to early implementers.

Implementers are encouraged to read Scope and Relationship to Other Specifications as a preface to the technical guidance in this implementation guide.

Current Release

This release aims to clarify CA:FeX v2.0.0 DFT to provide implementers with more streamlined content and support identifying which parts of the specification may apply to their context.

Use Cases and Definitions

For additional details on Use Case and Definitions, please see here.