New Zealand Rheumatic Fever FHIR Implementation Guide
1.0.0 - draft

New Zealand Rheumatic Fever FHIR Implementation Guide, published by Te Whatu Ora. This guide is not an authorized publication; it is the continuous build for version 1.0.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/tewhatuora/fhir-rheumatic-fever/ and changes regularly. See the Directory of published versions

CodeSystem: NZ-specific terminology in rheumatic fever data representation

Official URL: https://fhir-ig.digital.health.nz/rheumatic-fever/CodeSystem/nz-rheumaticfever-codesystem Version: 1.0.0
Active as of 2024-09-26 Computable Name: NzRheumaticFeverCodeSystem

This system defines standard codes used throughout this Implementation Guide for New Zealand rheumatic fever data representation

The codes defined in this CodeSystem are used throughout the rheumatic fever IG, including in resource profiles.

Originally it was sought to define these codes as concepts in the NZ Edition of SNOMED CT. However, this turned out to be unworkable due to restrictions imposed by SNOMED that only 'affiliate members' can access the contents of the SNOMED CT edition. As a consequence of this, applications cannot lookup nor access term definitions on NZHTS – NZ's official terminology server. This prevents FHIR validation of FHIR resources using (or meant to use) NZ edition SNOMED terms/codes.

Due to these restrictions this IG defines codes needed for NZ rheumatic fever data representation locally within the IG, in this CodeSystem.
Some of these codes re-use the original code numbers assigned in the NZ SNOMED edition in case this becomes publically accessible in future. The codes here are arranged in a 2-layer hierarchy which enables ValueSets segregated by purpose and help consumers understand the various purposes of the codes.

This Code system is referenced in the content logical definition of the following value sets:

Generated Narrative: CodeSystem nz-rheumaticfever-codesystem

This case-sensitive code system https://fhir-ig.digital.health.nz/rheumatic-fever/CodeSystem/nz-rheumaticfever-codesystem defines the following codes in an undefined hierarchy:

LvlCodeDisplayDefinition
1 meta-tags meta tags These codes are used to tag an instance via its meta.tag element
2   rf-nz rheumatic fever General purpose FHIR tag/classifier signifying FHIR information about an NZ rheumatic fever patient/case
1 condition-summary-codes These codes are used in NZ to summarise the condition diagnosis These code values originate in SNOMED CT but are defined only in the SNOMED NZ Edition
2   302471000210100 Rheumatic heart disease with absence of signs and symptoms of acute rheumatic fever (situation) Can be used to summarise the diagnosis of a patient with a rheumatic fever condition
2   299171000210109 History of acute rheumatic fever without heart disease Can be used to summarise the diagnosis of a patient with a rheumatic fever condition
1 diagnostic-certainty-codes Certainty of diagnosis classifiers As rheumatic fever can be difficult to diagnose, these codes provide a way to classify confidence in a particular case diagnosis
2   not-a-case not a case
2   under-investigation under investigation
2   borderline borderline
2   possible possible
2   probable probable
2   definite definite
1 rhd-severity-special-codes
2   300171000210106 Trivial (qualifier value)
2   59391000119102 History of heart valve repair (situation)
2   301561000210102 History of heart valve replacement (situation)
1 diagnosis-evidence-group-codes Observation diagnosis evidence groupings These code values originate in SNOMED CT, two being defined only in the SNOMED NZ Edition
2   439238004 Echocardiography test interpretation (observable entity)
2   447541000210107 New Zealand Jones Criteria Assessment (observable entity)
2   448011000210101 Evidence of preceding Streptococcus group A infection
1 diagnosis-component-NZ-special-concepts Special concepts in NZ RF diagnosis These code value originate in SNOMED CT, one being defined only in the SNOMED NZ Edition
2   448021000210106 Indolent carditis (disorder)
1 NZ-specific-role-codes
2   320731000210100 Support person Role code used in patient whanau care team (RfPatient.contact)
1 NZ-specific-injection-site-codes Specific injection sites in rheumatic fever secondary prophylaxis These code values originate in the SNOMED NZ Edition
2   299151000210101 Structure of left ventrogluteal region (body structure)
2   299161000210103 Structure of right ventrogluteal region (body structure)
2   299121000210105 Structure of left upper outer quadrant of buttock (body structure)
2   299141000210104 Structure of right upper outer quadrant of buttock (body structure)
1 nz-specific-medication-frequency-codes Specific medication frequency in rheumatic fever secondary prophylaxis This code value originates in the SNOMED NZ Edition
2   447521000210101 Every thirteen weeks (qualifier value)
1 nz-specific-medication-allergy-codes Specific allergy types relevant to rheumatic fever secondary prophylaxis These code values originate in the SNOMED NZ Edition
2   332571000210107 Allergy to benzathine penicillin
2   332581000210109 Allergy to pharmaceutical excipient
1 nz-national-system-identifier-type-codes Codes for differentiating types of external identifiers in national system slice of FHIR resource Identifier These codes signify identifiers which originate in a national system but synchronised into FHIR. The purpose of designating these codes is to provide a type discriminator for slicing Identifier in FHIR resource profiles
2   rfccs-careplan-id Identifies a CarePlan (case number) object in the NZ national RF Care Coordination System
2   rfccs-careplanactivity-id Identifies a CarePlanActivity object in the NZ national RF Care Coordination System
2   rfccs-condition-id Identifies a patient Condition object in the NZ national RF Care Coordination System
2   rfccs-careteam-id Identifies a CareTeam object in the NZ national RF Care Coordination System
2   rfccs-serviceappointment-id Identifies a patient appointment object in the NZ national RF Care Coordination System
2   rfccs-clinicalencounter-id Identifies a secondary prophylaxis appointment encounter object in the NZ national RF Care Coordination System
2   rfccs-observation-id Identifies an observation object in the NZ national RF Care Coordination System
2   episurv-number Identifies a notifiable disease surveillance case number in ESR's EpiSurv national system