Prinsipp for LOINC og SNOMED "samkoding"

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The use of LOINC "magic value" in combination with SNOMED CT codes

For exchanging vital signs observations using HL7 FHIR in Norway

Vital signs observations have predefined profiles defined by HL7 International. The goal of the HL7 vital signs profiles are:

The FHIR Vital Signs profile sets minimum expectations for the Observation resource to record, search and fetch the vital signs associated with a patient that include the primary vital signs plus additional measurements such as height, weight and BMI.

These profiles defines a LOINC "magic value" for use in Observation.code to tell what is being measured. The use of LOINC is problematic in Norway as the CodeSystem is not in common use by clinicians and the systems generally don't support LOINC codes. In Norway we would suggest to always exchange vital signs observations with an additional SNOMED CT code for better semantic interoperability. The following principles have been defined for the use of LOINC magic values and additional SNOMED CT coding in the Observation.code element:

1. A LOINC "magic value" is mandatory according to the HL7 vital signs profile
2. A SNOMED CT code representing 1:1 mapping to the LOINC "magic value" can be included in addition to the LOINC code to support better semantic interoperability in Norway
3. Any number of more specific SNOMED CT concept can be added to express more details concerning the observation
   1. When a more specific SNOMED CT code is added it must be a specialization of the SNOMED CT code defined as a 1:1 mapping to the LOINC "magic value"
   2. When a more specific SNOMED CT code is included the defined 1:1 mapping SNOMED CT code is mandatory
   3. In some cases a more specific SNOMED CT code can express semantics that could fit in the Observation.bodySite or Observation.method elements. In these cases the information should be included in the bodySite and method elements as well

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Legges til på denne siden: terminologibinding

[thomiz]

FORSLAG til revisjon: The use of LOINC "magic value" in combination with SNOMED CT codes

For exchanging vital signs observations using HL7 FHIR in Norway

Vital signs observations have predefined profiles defined by HL7 International. The goal of the HL7 vital signs profiles are:

The FHIR Vital Signs profile sets minimum expectations for the Observation resource to record, search and fetch the vital signs associated with a patient that include the primary vital signs plus additional measurements such as height, weight and BMI.

These profiles defines a LOINC "magic value" for use in Observation.code to tell what is being measured. The use of LOINC is challenging in Norway as the CodeSystem is not in common use by clinicians and IT-systems generally don't support LOINC codes. In Norway we would suggest to always exchange vital signs observations with an additional SNOMED CT code for better semantic interoperability. The following principles have been defined for the use of LOINC magic values and additional SNOMED CT coding in the Observation.code element:

1. A LOINC "magic value" is mandatory according to the HL7 vital signs profile
2. A SNOMED CT code representing the 1:1 mapping of the LOINC "magic value"can be included in addition to the LOINC code, to support better semantic interoperability in Norway. (This can include a concept that is a child to the concept that represents the 1:1 mapping).
3. Any number of more specific SNOMED CT concepts, including valid ECL statements, can be added to express more details concerning the observation
   1. When a more specific SNOMED CT code is added it must be a specialization of the SNOMED CT code defined as a 1:1 mapping to the LOINC "magic value"
   2. When a more specific SNOMED CT code is included the defined 1:1 mapping SNOMED CT code is mandatory
   3. In some cases a more specific SNOMED CT code or ECL can express semantics that could fit in the Observation.bodySite or Observation.method elements. In these cases the information should be included in the bodySite and method elements as well.

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Tok bort barn av 1:1 koding etter møte med HL7 Norge TSK

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TSK 2023-04-21:

• LOINC slicen gir liten klinisk verdi, SNOMED gir liten klinisk verdi

• Vi vinner det at vi kan legge over til SNOMED gradvis

  • Vi trenger 1:1 mapping for at man skal kunne angi at det skal være SNOMED underkoder som benyttes videre

• Vi trenger 1:1 for å være presis i forhold til hva vi faktisk uttrykker i instansen

• Påvirke vital-sign til å bli bedre internasjonalt

• Er 1:1 mappingen obligatorisk fra internasjonalt? (jeg tror det er best practice)

  • TSK ønsker at 1:1 mapping tas ut av prinsippene, men at vi tar et lite verdisett som kan brukes i "tredjeslicen"

• Ingen konklusjon

• SNOMED CT vitalsigns mapping

Kodeeksempel med tre koder i henhold til prinsipper

<code>
    <coding>
      <system value="http://loinc.org"/>
      <code value="8867-4"/> <!-- Dette er obligatorisk LOINC-->
      <display value="Heart rate"/>
    </coding>
    <coding>
      <system value="http://snomed.info/sct"/>
      <code value="364075005"/> <!-- 1:1 mapping til info -->
      <display value="Heart Rate"/>
    </coding>
    <coding>
      <system value="http://snomed.info/sct"/>
      <code value="78564009"/> <!-- Dette er puls, slicen bør begrenses i forhold til hvilke SNOMED CT begreper som skal benyttes-->
      <display value="Heart rate measured at systemic artery (observable entity)"/>
    </coding>
    <text value="Heartrate"/>
  </code>

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TSK 2023-05-26

Bør applisere prinsippet på vitale-parametere siden LOINC er obligatorisk for disse målingene.
Det er kanskje ikke relevant som et generelt prinsipp med mindre det endres noe.

Knytter denne saken til områdeprofilene og dokumentere prinsippet i forbindelse med no-domain.