External Terminologies Binding External Code Sets to attributes –Case 1 – Class is a specific observation in LOINC or HL7 Example: Number of brothers and sisters –Case 2 – Class is a generic observation Example: Observation as part of the patients clinical statement to record everything from current weight and age to existing medical conditions (MedDRA, SNOMED-CT, or LOINC) –Case 3 – EntityCode Country Code, Drug Code, Ingredient, Blood Product Code, Device Code, Vaccine? –Case 4 – Role Code Occupation and/or Job Code Context-Specific Conformance Profiles –Specify allowed bindings in Standard, constrain in Profile
Creating Value Sets from External Code Sets Case 1: CE attribute is constrained to one specific external terminology –Blood Product Type, Country Code Case 2: CE attribute can be either external terminology A or B –Example: Drug Code (RxNorm or NDC) –Can not mix within a set, class, or report Case 3: LOINC concept constrains Observation.code and Answer List in LOINC constrains Observation.value Case 4: HL7 concept constrains Observation.code and SNOMED-CT or MedDRA constrains Observation.value –Reaction.code and Reaction.value –ConcurrentObservation.code (can mix LOINC and SNOMED) Case 5: CE attribute constrained to one value –Autopsy.code
E2B, MedWatch, VAERS codes Add to LOINC or HL7? May vary by report type (i.e, drug vs. device) –Represented as Observations (Summaries, judgments) CaseSeriousness ReactionRelatedness.code Severity.code Outcome.code Interpretation.code Intervention.code Indication.code ActionTaken.code InterventionCharacterization.code DeviceEvaluationObservation.code –Represented as Acts Other Report Types Document Types –More
Observation Code and Value Datatypes Code ST, The plain code symbol defined by the code system. For example, "784.0" is the code symbol of the ICD-9 code "784.0" for headache. codeSystem UID, Specifies the code system that defines the code. codeSystemName ST, The common name of the coding system. codeSystemVersion ST, If applicable, a version descriptor defined specifically for the given code system. displayName ST, A name or title for the code, under which the sending system shows the code value to its users. originalText ED, The text or phrase used as the basis for the coding. Translation SET, A set of other concept descriptors that translate this concept descriptor into other code systems.
To LOINC-ize or to HL7-ize? Observation.code LOINCHL7 code = (under Observtiontype) codeSystem =LOINC OID HL7 ActCode OID codeSystemVersion = x.x x.x displayName =DrugCharacterizationCode DrugCharacterizationCode Observation.value code = S,I, or C S,I, or C codeSystem =LOINC? HL7 ObservationValue OID codeSystemVersion =x.x x.x displayName =Suspect, Interacting or Suspect, Interacting or Concommittant