Terminology Approach


This version of the PS-CA Implementation Guide has been superceded by version 0.0.4. Other releases of the PS-CA Implementation Guide may be found at Guides.


Approach to Value Sets

The scope of PS-CA value sets is confined to HL7 IPS FHIR profiles that have existing terminology bindings defined for data elements. The following principles were developed to guide the definition of the value sets required for the PS-CA profiles.

The development and definition of PS-CA value sets was completed under the following principles:

  • must support semantic interoperability and implementation in Canada over the short- and long-term.
  • must align and support national terminology policy such as SNOMED CT Canadian Edition, Canadian Clinical Drug Data Set (CCDD), and pan-Canadian LOINC Observation Code Database (pCLOCD) (see below).
  • must accommodate the requirements of jurisdictions where feasible.
  • must take into consideration the guidance from the Global Digital Health Partnership (GDHP), which recommends the use of SNOMED CT in specific clinical domains.
  • must take into consideration the terminology binding strength of existing required value sets to ensure there is no disruption in interoperability.
  • must take into consideration that FHIR is a data interoperability standard and value sets developed are suited for data exchange and may be broader than value sets used at the point of care.
  • must include clinical review and stakeholder input and quality assurance processes.
  • must include formal documentation of the approach, decisions, characteristics of these value sets, and maintenance processes.
  • must identify opportunities for multi-use value sets, where a single value set is relevant for multiple data elements (create once, use many times) will be identified and implemented.

Terminologies and Classifications - Current and Future State

Current state health system clinical terminologies and classifications identified as national standards and in use across jurisdictions include:

  • SNOMED CT Canadian Edition (SNOMED CT-CA)
  • International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Canada (ICD-10-CA)
  • International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)
  • Canadian Classification of Health Interventions (CCI)
  • Logical Observation Identifiers Names and Codes (LOINC)
  • pan-Canadian LOINC Observation Code Database (pCLOCD)
  • Canadian Clinical Drug Data Set (CCDD)
  • HL7 Vocabulary

In addition, across jurisdictions there is extensive use of free-text and some locally defined term sets used for EMR data capture.

In future, it is expected these major terminologies and classifications will continue to exist and that there will be an increase in the use of SNOMED CT-CA in place of free-text or locally defined term sets for EMR data exchange and data capture.