Mention extension

The mention extension links one field of a FHIR Extraction resource to the words in the clinical note that support its value. It is a complex extension: it has no value of its own, only sub-extensions. Every value points back to the note shows how to use it.

Definition

Property	Value
Canonical URL	`https://docs.corti.ai/fhir/StructureDefinition/mention`
FHIR version	R4 (4.0.1)
Context	Condition, AllergyIntolerance, FamilyMemberHistory, Procedure, Observation, Patient, Encounter
Cardinality on a resource	`0..*`: one mention extension per field that has evidence

Systems that do not know the extension can ignore it. It never changes the meaning of the resource.

Sub-extensions

Sub-extension `url`	Cardinality	Value	Definition
`field`	`1..1`	`valueString`	The field the mention supports, for example `code` or `valueQuantity`
`evidence`	`1..*`	nested `start`, `end`, `text`, `sectionId`, `sectionStart`, `sectionEnd`	One span of the note that supports the field
`evidence.start`	`1..1`	`valueInteger`	Character offset where the span starts, counted from the start of the full note
`evidence.end`	`1..1`	`valueInteger`	Character offset where the span ends. The character at `end` is not part of the span.
`evidence.text`	`0..1`	`valueString`	The words of the note between `start` and `end`
`evidence.sectionId`	`0..1`	`valueString`	The `id` of the `context` section the span comes from
`evidence.sectionStart`	`0..1`	`valueInteger`	Character offset where the span starts, counted from the start of that section’s title and body joined together
`evidence.sectionEnd`	`0..1`	`valueInteger`	Character offset where the span ends in that section’s title and body. The character at `sectionEnd` is not part of the span.

start and end count characters of the full note. A context string is the note as it is. With context sections, the note is every section written as Title: on its own line, then the body, then a blank line. Only spans from a request with sections carry sectionId, sectionStart, and sectionEnd, which count characters of the section’s title followed directly by its body, so you can look up a span without rebuilding the note. A span that crosses from one section into the next has no section offsets.

Field values

field holds the R4 element name the mention supports. A choice element such as onset[x] uses its base name (onset), whichever type the resource carries. Nested elements use a dotted path.

Resource	`field` values
Condition	`abatement`, `bodySite`, `category`, `clinicalStatus`, `code`, `onset`, `severity`, `stage`, `verificationStatus`
AllergyIntolerance	`category`, `clinicalStatus`, `code`, `criticality`, `lastOccurrence`, `onset`, `reaction`, `type`, `verificationStatus`
FamilyMemberHistory	`age`, `condition.code`, `condition.onset`, `relationship`, `sex`, `status`
Procedure	`bodySite`, `category`, `code`, `performed`, `performer`, `status`
Observation	`bodySite`, `code`, `effective`, `interpretation`, `status`, `valueCodeableConcept`, `valueInteger`, `valueQuantity`, `valueQuantity.unit`, `valueRatio`, `valueRatio.numerator.unit`
Patient	`birthDate`, `gender`
Encounter	`class`, `period`, `priority`, `reason`, `status`

A mention can exist for a field the resource leaves out. For example, a time stated as “last month” grounds lastOccurrence even though that field only accepts dates and is omitted.

Example

{
  "url": "https://docs.corti.ai/fhir/StructureDefinition/mention",
  "extension": [
    { "url": "field", "valueString": "code" },
    {
      "url": "evidence",
      "extension": [
        { "url": "start", "valueInteger": 5 },
        { "url": "end", "valueInteger": 11 },
        { "url": "text", "valueString": "asthma" }
      ]
    }
  ]
}

Alternative extension: other codes that could also fit a field
FHIR datatypes: how extensions sit on a resource

Clinical Text Generation

Medical Coding

FHIR Extraction

Clinical Assistant

Definition

Sub-extensions

Field values

Example

​Definition

​Sub-extensions

​Field values

​Example

​Related pages

Definition

Sub-extensions

Field values

Example

Related pages