This page is part of the FHIR Specification (v1.8.0: STU 3 Draft). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions . Page versions: R5 R4B R4 R3 R2
Definitions for the ldlcholesterol Profile.
Observation(LDLCholesterol) | |
Definition | Group of elements for LDL Cholesterol result. |
Control | 1..1 |
Alternate Names | Vital Signs, Measurement, Results, Tests |
Comments | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as lab reports, etc. |
Invariants | Defined on this element dom-1: If the resource is contained in another resource, it SHALL NOT contain any narrative (xpath: not(parent::f:contained and f:text)) dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (xpath: not(parent::f:contained and f:contained)) dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource (xpath: not(exists(for $id in f:contained/*/@id return $id[not(ancestor::f:contained/parent::*/descendant::f:reference/@value=concat('#', $id))]))) dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (xpath: not(exists(f:contained/*/f:meta/f:versionId)) and not(exists(f:contained/*/f:meta/f:lastUpdated))) obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (xpath: not(exists(f:dataAbsentReason)) or (not(exists(*[starts-with(local-name(.), 'value')])))) obs-7: If code is the same as a component code then the value element associated with the code SHALL NOT be present (xpath: not(exists(f:value)) or not(count(for $coding in f:code/f:coding return parent::*/f:component/f:code/f:coding[f:code/@value=$coding/f:code/@value and f:system/@value=$coding/f:system/@value])=0)) |
Observation.id | |
Definition | The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes. |
Control | 0..1 |
Type | id |
Comments | The only time that a resource does not have an id is when it is being submitted to the server using a create operation. |
Observation.meta | |
Definition | The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content may not always be associated with version changes to the resource. |
Control | 0..1 |
Type | Meta |
Observation.implicitRules | |
Definition | A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. |
Control | 0..1 |
Type | uri |
Is Modifier | true |
Comments | Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element as much as possible. |
Observation.language | |
Definition | The base language in which the resource is written. |
Control | 0..1 |
Terminology Binding | A human language. The codes SHALL be taken from Common Languages; other codes may be used where these codes are not suitable |
Type | code |
Comments | Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute). |
Observation.text | |
Definition | A human-readable narrative that contains a summary of the resource, and may be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety. |
Control | 0..1 This element is affected by the following invariants: dom-1 |
Type | Narrative |
Alternate Names | narrative, html, xhtml, display |
Comments | Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded in formation is added later. |
Observation.contained | |
Definition | These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope. |
Control | 0..* |
Type | Resource |
Alternate Names | inline resources, anonymous resources, contained resources |
Comments | This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again. |
Observation.extension (http://hl7.org/fhir/StructureDefinition/lipid-report-ldl-chol-calculated) | |
Definition | True if the LDL value is calculated from Chol, Trig, and HDLC. |
Control | 0..1 This element is affected by the following invariants: ele-1 |
Type | (Extension Type: boolean) |
Comments | It's definitely better that whether the LDL was calculated or not comes from the LOINC code. But this is defined to exercise the extension machinery in the publication tooling, and to make this comment. Actually, the location is odd too - it would probably be on the root observation, but this is for testing purposes. |
Invariants | Defined on this element ele-1: All FHIR elements must have a @value or children (xpath: @value|f:*|h:div) ext-1: Must have either extensions or value[x], not both (xpath: exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])) |
Observation.modifierExtension | |
Definition | May be used to represent additional information that is not part of the basic definition of the resource, and that modifies the understanding of the element that contains it. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. |
Control | 0..* |
Type | Extension |
Is Modifier | true |
Alternate Names | extensions, user content |
Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
Observation.identifier | |
Definition | A unique identifier for the simple observation instance. |
Control | 0..* |
Type | Identifier |
Requirements | Allows observations to be distinguished and referenced. |
Observation.status | |
Definition | The status of the result value. |
Control | 1..1 |
Terminology Binding | Codes providing the status of an observation. The codes SHALL be taken from ObservationStatus |
Type | code |
Is Modifier | true |
Requirements | Need to track the status of individual results. Some results are finalized before the whole report is finalized. |
Observation.category | |
Definition | A code that classifies the general type of observation being made. |
Control | 0..* |
Terminology Binding | Codes for high level observation categories . For example codes, see Observation Category Codes |
Type | CodeableConcept |
Requirements | Used for filtering what observations are retreived and displayed. |
Comments | There may be multiple axis of categoriization depending on the context or use case for retrieving or displaying the resource. The level of granularity is defined by the category concepts in the value set. |
Observation.code | |
Definition | LDL Cholesterol -measured or calculated per code. |
Control | 1..1 |
Terminology Binding | LDL Cholesterol codes - measured or calculated The codes SHALL be taken from LDLCodes |
Type | CodeableConcept |
Must Support | true |
Requirements | Knowing what kind of observation is being made is essential to understanding the observation. |
Observation.subject | |
Definition | The patient, or group of patients, location, or device whose characteristics (direct or indirect) are described by the observation and into whose record the observation is placed. Comments: Indirect characteristics may be those of a specimen, fetus, donor, other observer (for example a relative or EMT), or any observation made about the subject. |
Control | 0..1 |
Type | Choice of: Reference(Patient), Reference(Group), Reference(Device), Reference(Location) |
Requirements | Observations have no value if you don't know who or what they're about. |
Comments | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. If the target of the observation is different than the subject, the general extension observation-focal-subject. may be used. However, the distinction between the patient's own value for an observation versus that of the fetus, or the donor or blood product unit, etc., are often specified in the observation code. |
Observation.encounter | |
Definition | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. |
Control | 0..1 |
Type | Reference(Encounter) |
Requirements | For some observations it may be important to know the link between an observation and a particular encounter. |
Observation.effective[x] | |
Definition | The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself. |
Control | 0..1 |
Type | Choice of: dateTime, Period |
[x] Note | See Choice of Data Types for further information about how to use [x] |
Requirements | Knowing when an observation was deemed true is important to its relevance as well as determining trends. |
Comments | At least a date should be present unless this observation is a historical report. |
Observation.issued | |
Definition | The date and time this observation was made available to providers, typically after the results have been reviewed and verified. |
Control | 0..1 |
Type | instant |
Comments | Updated when the result is updated. |
Observation.performer | |
Definition | Who was responsible for asserting the observed value as "true". |
Control | 0..* |
Type | Choice of: Reference(Practitioner), Reference(Organization), Reference(Patient), Reference(RelatedPerson) |
Requirements | May give a degree of confidence in the observation and also indicates where follow-up questions should be directed. |
Observation.valueQuantity | |
Definition | LDL Cholesterol value. If a result is not available, use the comments field. |
Control | 0..1 This element is affected by the following invariants: obs-7 |
Type | Quantity |
Must Support | true |
Requirements | An observation exists to have a value, though it may not if it is in error, or it represents a group of observations. |
Comments | Normally, an observation will have either a value or a set of related observations. A few observations (e.g. Apgar score) may have both a value and related observations (for an Apgar score, the observations from which the measure is derived). If a value is present, the datatype for this element should be determined by Observation.code. This element has a variable name depending on the type as follows: valueQuantity, valueCodeableConcept, valueString, valueRange, valueRatio, valueSampledData, valueAttachment, valueTime, valueDateTime, or valuePeriod. (The name format is "'value' + the type name" with a capital on the first letter of the type). If the data element is usually coded or if the type associated with the Observation.value defines a coded value, use CodeableConcept instead of string datatype even if the value is uncoded text. A value set is bound to the ValueCodeableConcept element. For boolean values use valueCodeableConcept and select codes from HL7 Version 2 Table 0136. These "yes/no" concepts can be mapped to the display name "true/false" or other mutually exclusive terms that may be needed. For further discussion and examples see the notes section below. |
Observation.dataAbsentReason | |
Definition | Provides a reason why the expected value in the element Observation.value[x] is missing. |
Control | 0..1 This element is affected by the following invariants: obs-6 |
Terminology Binding | Codes specifying why the result (Observation.value[x]) is missing. The codes SHALL be taken from Observation Value Absent Reason; other codes may be used where these codes are not suitable |
Type | CodeableConcept |
Requirements | For many results it is necessary to handle exceptional values in measurements. |
Comments | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
Observation.interpretation | |
Definition |
|
Control | 0..1 |
Terminology Binding | Codes identifying interpretations of observations. The codes SHALL be taken from Observation Interpretation Codes; other codes may be used where these codes are not suitable |
Type | CodeableConcept |
Must Support | true |
Requirements | For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result. |
Alternate Names | Abnormal Flag |
Observation.comment | |
Definition | Comments about result. |
Control | 0..1 |
Type | string |
Must Support | true |
Requirements | Need to be able to provide free text additional information. |
Observation.bodySite | |
Definition | Indicates the site on the subject's body where the observation was made (i.e. the target site). |
Control | 0..1 |
Terminology Binding | Codes describing anatomical locations. May include laterality. For example codes, see SNOMED CT Body Structures |
Type | CodeableConcept |
Requirements | Knowing where the observation is made is important for tracking if multiple sites are possible. |
Comments | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use The standard extension body-site-instance. |
Observation.method | |
Definition | Indicates the mechanism used to perform the observation. |
Control | 0..1 |
Terminology Binding | Methods for simple observations. For example codes, see Observation Methods |
Type | CodeableConcept |
Requirements | In some cases, method can impact results and is thus used for determining whether results can be compared or determining significance of results. |
Comments | Only used if not implicit in code for Observation.code. |
Observation.specimen | |
Definition | The specimen that was used when this observation was made. |
Control | 0..1 |
Type | Reference(Specimen) |
Comments | Observations are not made on specimens themselves; they are made on a subject, but usually by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
Observation.device | |
Definition | The device used to generate the observation data. |
Control | 0..1 |
Type | Choice of: Reference(Device), Reference(DeviceMetric) |
Comments | An extension should be used if further typing of the device is needed. Devices used to support obtaining an observation can be represented using either extension or through the Observation.related element. |
Observation.referenceRange | |
Definition | Guidance on how to interpret the value by comparison to a normal or recommended range. |
Control | 1..1 |
Type | BackboneElement |
Must Support | true |
Requirements | Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts. |
Comments | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g. specific to the patient's age, gender, weight and other factors), but this may not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
Invariants | Defined on this element ele-1: All FHIR elements must have a @value or children (xpath: @value|f:*|h:div) obs-3: Must have at least a low or a high or text (xpath: (exists(f:low) or exists(f:high)or exists(f:text))) |
Observation.referenceRange.id | |
Definition | unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. |
Control | 0..1 |
Type | string |
Observation.referenceRange.extension | |
Definition | May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. |
Control | 0..* |
Type | Extension |
Alternate Names | extensions, user content |
Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
Observation.referenceRange.modifierExtension | |
Definition | May be used to represent additional information that is not part of the basic definition of the element, and that modifies the understanding of the element that contains it. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. |
Control | 0..* |
Type | Extension |
Is Modifier | true |
Alternate Names | extensions, user content, modifiers |
Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
Observation.referenceRange.low | |
Definition | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). |
Control | 0..0 This element is affected by the following invariants: obs-3 |
Type | Quantity(SimpleQuantity) |
Observation.referenceRange.high | |
Definition | <3.0 mmol/L. |
Control | 1..1 This element is affected by the following invariants: ele-1 |
Type | Quantity(SimpleQuantity) |
Comments | Per Australian NHF Recommendations. |
Fixed Value | <valueQuantity xmlns="http://hl7.org/fhir"> <value value="3.0"/> </valueQuantity> |
Invariants | Defined on this element ele-1: All FHIR elements must have a @value or children (xpath: @value|f:*|h:div) qty-3: If a code for the unit is present, the system SHALL also be present (xpath: not(exists(f:code)) or exists(f:system)) sqty-1: The comparator is not used on a SimpleQuantity (xpath: not(exists(f:comparator))) |
Observation.referenceRange.meaning | |
Definition | Range is a recommended range. |
Control | 0..0 |
Terminology Binding | Code for the meaning of a reference range. For example codes, see Observation Reference Range Meaning Codes |
Type | CodeableConcept |
Requirements | Need to be able to say what kind of reference range this is - normal, recommended, therapeutic, etc - for proper interpretation. |
Comments | This SHOULD be populated if there is more than one range. If this element is not present then the norma population is assumed. |
Observation.referenceRange.age | |
Definition | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. |
Control | 0..0 |
Type | Range |
Requirements | Some analytes vary greatly over age. |
Observation.referenceRange.text | |
Definition | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of 'normals'. |
Control | 0..1 |
Type | string |
Observation.related | |
Definition | A reference to another resource (usually another Observation) whose relationship is defined by the relationship type code. |
Control | 0..0 |
Type | BackboneElement |
Requirements | Normally, an observation will have either a value or a set of related observations. A few observations (e.g. Apgar score) may have both a value and a set of related observations or sometimes QuestionnaireResponse from which the measure is derived. |
Comments | For a discussion on the ways Observations can assembled in groups together see Notes below. |
Invariants | Defined on this element ele-1: All FHIR elements must have a @value or children (xpath: @value|f:*|h:div) |
Observation.related.id | |
Definition | unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. |
Control | 0..1 |
Type | string |
Observation.related.extension | |
Definition | May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. |
Control | 0..* |
Type | Extension |
Alternate Names | extensions, user content |
Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
Observation.related.modifierExtension | |
Definition | May be used to represent additional information that is not part of the basic definition of the element, and that modifies the understanding of the element that contains it. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. |
Control | 0..* |
Type | Extension |
Is Modifier | true |
Alternate Names | extensions, user content, modifiers |
Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
Observation.related.type | |
Definition | A code specifying the kind of relationship that exists with the target resource. |
Control | 0..1 |
Terminology Binding | Codes specifying how two observations are related. The codes SHALL be taken from ObservationRelationshipType |
Type | code |
Requirements | A relationship type SHOULD be provided. |
Comments | "derived-from" is only logical choice when referencing QuestionnaireAnswer resource. |
Observation.related.target | |
Definition | A reference to the observation or QuestionnaireResponse resource that is related to this observation. |
Control | 1..1 |
Type | Choice of: Reference(Observation), Reference(QuestionnaireResponse), Reference(Sequence) |
Observation.component | |
Definition | Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. |
Control | 0..* |
Type | BackboneElement |
Requirements | Component observations share the same attributes in the Observation resource as the primary observation and are always treated a part of a single observation (they are not separable). However, the reference range for the primary observation value is not inherited by the component values and is required when appropriate for each component observation. |
Comments | For a discussion on the ways Observations can assembled in groups together see Notes below. |
Invariants | Defined on this element ele-1: All FHIR elements must have a @value or children (xpath: @value|f:*|h:div) |
Observation.component.id | |
Definition | unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. |
Control | 0..1 |
Type | string |
Observation.component.extension | |
Definition | May be used to represent additional information that is not part of the basic definition of the element. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. |
Control | 0..* |
Type | Extension |
Alternate Names | extensions, user content |
Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
Observation.component.modifierExtension | |
Definition | May be used to represent additional information that is not part of the basic definition of the element, and that modifies the understanding of the element that contains it. Usually modifier elements provide negation or qualification. In order to make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. |
Control | 0..* |
Type | Extension |
Is Modifier | true |
Alternate Names | extensions, user content, modifiers |
Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
Observation.component.code | |
Definition | Describes what was observed. Sometimes this is called the observation "code". |
Control | 1..1 |
Terminology Binding | Codes identifying names of simple observations. For example codes, see LOINC Codes |
Type | CodeableConcept |
Requirements | Knowing what kind of observation is being made is essential to understanding the observation. |
Observation.component.value[x] | |
Definition | The information determined as a result of making the observation, if the information has a simple value. |
Control | 0..1 |
Type | Choice of: Quantity, CodeableConcept, string, Range, Ratio, SampledData, Attachment, time, dateTime, Period |
[x] Note | See Choice of Data Types for further information about how to use [x] |
Requirements | An observation exists to have a value, though it may not if it is in error, or it represents a group of observations. |
Comments | Normally, an observation will have either a value or a set of related observations. A few observations (e.g. Apgar score) may have both a value and related observations (for an Apgar score, the observations from which the measure is derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For boolean values use valueCodeableConcept and select codes from <http://hl7.org/fhir/ValueSet/v2-0136> (These "yes/no" concepts can be mapped to the display name "true/false" or other mutually exclusive terms that may be needed"). The element, Observation.value[x], has a variable name depending on the type as follows: valueQuantity, valueCodeableConcept, valueRatio, valueChoice, valuePeriod, valueSampleData, or valueString (The name format is "'value' + the type name" with a capital on the first letter of the type). |
Observation.component.dataAbsentReason | |
Definition | Provides a reason why the expected value in the element Observation.value[x] is missing. |
Control | 0..1 This element is affected by the following invariants: obs-6 |
Terminology Binding | Codes specifying why the result (Observation.value[x]) is missing. The codes SHALL be taken from Observation Value Absent Reason; other codes may be used where these codes are not suitable |
Type | CodeableConcept |
Requirements | For many results it is necessary to handle exceptional values in measurements. |
Comments | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
Observation.component.interpretation | |
Definition | The assessment made based on the result of the observation. Intended as a simple compact code often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. Otherwise known as abnormal flag. |
Control | 0..1 |
Terminology Binding | Codes identifying interpretations of observations. The codes SHALL be taken from Observation Interpretation Codes; other codes may be used where these codes are not suitable |
Type | CodeableConcept |
Requirements | For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result. |
Alternate Names | Abnormal Flag |
Comments | The component interpretation is applies only to the indivual component value. For an overall interpretation all components together use Observation.interpretation element. |
Observation.component.referenceRange | |
Definition | Guidance on how to interpret the value by comparison to a normal or recommended range. |
Control | 0..* |
Type | See Observation:ldlcholesterol.referenceRange |
Requirements | Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts. |
Comments | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g. specific to the patient's age, gender, weight and other factors), but this may not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |