Implementation Guidance > Conformance Rules

Conformance Rules

FHIR is a general purpose specification and imposes no particular requirements on implementers to support specific resources, operations, search parameters or other capabilities. To achieve interoperability in a particular domain, it's important that implementors make similar decisions about what FHIR capabilities those systems will support. FHIR uses the CapabilityStatement resource to define the actual or expected capabilities of a particular system.

MustSupport Flag

FHIR standard utilizes MustSupport flag to identify data elements that implementers must support in order to produce or consume FHIR resources in some meaningful way. Please refer to the guidance below:

Submitting Data

When submitting data to Ontario Health, the source system must demonstrate that it is capable of providing the elements marked with the "MustSupport" flag in accordance with the profile definition and associated business rules. Each FHIR resource instance may not always contain these elements.

Elements without the "MustSupport" flag should not be included in a FHIR submission. If included it won't be stored in DHDR Solution.

Consuming Data

Elements marked with "MustSupport" will be supported in accordance with the definition in the profiles for the DHDR. Consuming applications SHALL be capable of processing resources containing MustSupport data elements without generating an error or causing the application to fail. Consuming applications SHOULD be capable of handling the MustSupport data elements in a meaningful way (e.g. store it, use it in subsequent workflow or business function), and SHALL be able to process instances containing MustSupport data elements asserting missing information. Elements without the "MustSupport" flag when receiving from DHDR might not be stored, viewed, or otherwise processed by the receiving application unless there is implementation guidance to indicate that the element is considered optional, in which case it should be displayed, stored, or otherwise processed if possible.

Data Formatting

Letter Case Information in DHDR is stored as mixed case and information is preserved in the format provided by the source (e.g. ALL UPPER CASE, Mixed Case, or a mix). DHDR consumers MAY apply data formatting rules where there is a local requirement to standardize information to a consistent format.

Extended Character Set

Information within Ontario’s EHR assets includes UTF-8 to support extended characters beyond standard ASCII/ANSI character set including French characters.