How to use this specification

The Approach

This specification uses a different approach to profiling and how the constraints for a particular business use case are applied to the FHIR resources.

Profiles

This implementation has no business specific profiles and uses the CareConnect level two profiles with additional textual constraints and guidance. This additional text will form part of any conformance testing implemented later in development.

Format of Textual Constraints and Guidance

Each Resource used in a FHIR message, bundle or other FHIR structure is documented as a table generated from a rendered version of the CareConnect profile being used as the level 2 profile for the resource. The tables are linked to each other in the same structure that would be used in the XML or JSON instance. The table has links to various things such as the FHIR standard, profiles and ValueSets etc.

The Format of the Guidance

Each guidance page has the following format

  • A diagram of the FHIR message, Bundle or FHIR Structure to illustrate the resources used and references between the resources.
  • Text which indicates the FHIR resource used, the level 2 profile used and any level 3 profile (if used). Note: in most implementations that use this approach there will never be any level 3 profiles.
  • Links to allow the ability to switch from the default view, one that shows only the FHIR resource elements that are used in the FHIR resource to a view of all the elements in the FHIR resource.
  • A series of tables one for each CareConnect profile used. These are linked to each other following the references as per the diagram and provide links to the NHS Digital FHIR server and the HL7 FHIR standard. The tables give the constraints and guidance for the resource above what is already enforced in the CareConnect level 2 profile. The table for each resource used in the instance is contained in a section on this page with the heading Mapping for “Resource Name” for example Mapping for Patient.

The Mapping Table Format

The table has five columns with the following headings:

  1. Name
  2. Card
  3. Type
  4. Conformance
  5. Constraints and Mapping

Name

This column contains the resource name and nested below the FHIR resource elements. the nesting is illustrated using hyphens for example

- level 1 - - level 2 - - - level 3 etc etc

The elements are shown as per the NHS Digital FHIR server rendering and may not include every child element.

Card

This is the cardinally of the element from a business perspective and may be tighter than the CareConnect profile. To follow constraint rule,s it will never be less constrained than the CareConnect profile.

Conformance

This is the conformance of FHIR element from the business perspective. It is either mandatory, required or optional these are defined as below:

  • Mandatory - The FHIR element MUST contain a value - Note the business may allow values such as “not known” or “ no information” the allowed value will be documented in the Constraints and mapping column.
  • Required - The sender MUST include the information or alternative values as defined by the business use case, if available on the sending system .
  • Optional - This element may be populated or not dependent on the sending system’s capability.

Note: These are the default behaviours which may vary from use case to use case. Any variation will be documented in the relevant specification.

Type

This is the type of element as defined by the FHIR standard. The type will link to the relevant page in the correct version of the FHIR standard.

Constraints and Mapping

This column provides various information as below:

  • The annotation for the FHIR element as contained in the FHIR profile - this appear in black
  • Additional constraints and guidance for population of the FHIR element - this appears in red
  • The mapping to the business data item - this appears in red bold for example Maps to Patient national identifier.
Tags: fhir