Quality Measure Implementation Guide
2.0.0-ballot - STU 2 Ballot

Quality Measure Implementation Guide - Downloaded Version null See the Directory of published versions

## Measure: EXM55 - Median Emergency Department Visit Duration (Experimental)

Official URL: http://hl7.org/fhir/uv/cqm/Measure/EXM55-FHIR | Version: 5.0.0 | Highlight text changes?
Standards status: Informative Active as of 2025-08-13 | Computable Name: EXM55
Other Identifiers: http://example.org/fhir/cqi/ecqm/Measure/Identifier/exm#55 (use: official, ), OID:2.16.840.1.113883.4.642.40.61.29.8
Usage: Clinical Venue: EH

This example illustrates a continuous variable measure represented as a FHIR eCQM

Metadata
Title | EXM55 - Median Emergency Department Visit Duration
Version | 5.0.0
Identifier | 55
Identifier | urn:oid:2.16.840.1.113883.4.642.40.61.29.8
Effective Period | 2018-01-01 through 2018-12-31
Approval Date | 2019-03-08
Last Review Date | 2019-03-08
Experimental | true
Use Context | Clinical Venue = EH
Jurisdiction | 001 from http://unstats.un.org/unsd/methods/m49/m49.htm
Topic | Health Quality Measure Document
Steward (Publisher) | HL7 International / Clinical Quality Information
Description | This example illustrates a continuous variable measure represented as a FHIR eCQM
Measure Basis | Encounter
Measure Scoring | Continuous Variable
Improvement Notation | Decreased score indicates improvement
Measure Type | process from http://terminology.hl7.org/CodeSystem/measure-type
Measure Group (Rate) (ID: primary)
Stratifier | Code: Stratification 1
Stratifier | Code: Stratification 2
Stratifier | Code: Stratification 3
Measure Logic
Primary Library | EXM55 - Median Emergency Department Visit Duration Library (Example Continuous Variable Measure Library)
Contents | Population Criteria Logic Definitions Terminology Dependencies Data Requirements Parameters
Population Criteria
Measure Group (Rate) (ID: primary)
Stratifier
    define "Stratification 1" :
      "Inpatient Encounter" Encounter
        where not (PrincipalDiagnosis(Encounter).code in "Psychiatric/Mental Health Patient")
Definition
Stratifier
    define "Stratification 2" :
      "Inpatient Encounter" Encounter
        where PrincipalDiagnosis(Encounter).code in "Psychiatric/Mental Health Patient"
Definition
Stratifier
    define "Stratification 3" :
      "Inpatient Encounter" Encounter
        where PrincipalDiagnosis(Encounter) is null
Definition
Logic Definitions
Logic Definition | Library Name: FHIRHelpers
    /*
    @description: Converts the given [Period](https://hl7.org/fhir/datatypes.html#Period)
    value to a CQL DateTime Interval
    @comment: If the start value of the given period is unspecified, the starting
    boundary of the resulting interval will be open (meaning the start of the interval
    is unknown, as opposed to interpreted as the beginning of time).
    */
    define function ToInterval(period FHIR.Period):
        if period is null then
            null
        else
            if period."start" is null then
                Interval(period."start".value, period."end".value]
            else
                Interval[period."start".value, period."end".value]
Logic Definition | Library Name: FHIRHelpers
    /*
    @description: Converts the given FHIR [CodeableConcept](https://hl7.org/fhir/datatypes.html#CodeableConcept) value to a CQL Concept.
    */
    define function ToConcept(concept FHIR.CodeableConcept):
        if concept is null then
            null
        else
            System.Concept {
                codes: concept.coding C return ToCode(C),
                display: concept.text.value
            }
Logic Definition | Library Name: FHIRHelpers
    /*
    @description: Converts the given FHIR [Coding](https://hl7.org/fhir/datatypes.html#Coding) value to a CQL Code.
    */
    define function ToCode(coding FHIR.Coding):
        if coding is null then
            null
        else
            System.Code {
              code: coding.code.value,
              system: coding.system.value,
              version: coding.version.value,
              display: coding.display.value
            }
Logic Definition | Library Name: FHIRHelpers
    define function ToString(value string): value.value
Logic Definition | Library Name: FHIRHelpers
    define function ToString(value EncounterStatus): value.value
Logic Definition | Library Name: EXM55
    define "Inpatient Encounter" :
      ["Encounter"] Encounter
        where LengthInDays(Encounter.period) <= 120
          and Encounter.period ends during "Measurement Period"
Logic Definition | Library Name: EXM55
    define "Stratification 3" :
      "Inpatient Encounter" Encounter
        where PrincipalDiagnosis(Encounter) is null
Logic Definition | Library Name: EXM55
    define "Stratification 2" :
      "Inpatient Encounter" Encounter
        where PrincipalDiagnosis(Encounter).code in "Psychiatric/Mental Health Patient"
Logic Definition | Library Name: EXM55
    define "Measure Population Exclusion" :
      "Inpatient Encounter" Encounter
        with ["Encounter" : "Emergency Department Visit"] ED
          such that ED.period ends 1 hour or less before start of Encounter.period
            and ED.status = 'finished'
            and ED.hospitalization.admitSource in "Hospital Settings"
Logic Definition | Library Name: EXM55
    define "Stratification 1" :
      "Inpatient Encounter" Encounter
        where not (PrincipalDiagnosis(Encounter).code in "Psychiatric/Mental Health Patient")
Logic Definition | Library Name: EXM55
    define "Initial Population" :
      "Inpatient Encounter" Encounter
        with ["Encounter" : "Emergency Department Visit"] ED
         such that ED.status = 'finished'
           and ED.period ends 1 hour or less before start of Encounter.period
Logic Definition | Library Name: EXM55
    define "Measure Population" :
      "Initial Population"
Logic Definition | Library Name: EXM55
    define function "LengthInDays"(Value Interval<DateTime>):
    	difference in days between start of Value and end of Value
Logic Definition | Library Name: EXM55
    define function "PrincipalDiagnosis"(Encounter Encounter):
    	(singleton from (Encounter.diagnosis D where D.use ~ ToConcept("Billing") and D.rank.value = 1)) PD
    		return singleton from ([Condition: id in "GetId"(PD.condition.reference)])
Logic Definition | Library Name: EXM55
    define function "GetId"(uri String):
    	Last(Split(uri, '/'))
Logic Definition | Library Name: EXM55
    define function "Measure Observation" (Encounter "Encounter" ) :
      duration in minutes of "Related ED Visit"(Encounter).period
Logic Definition | Library Name: EXM55
    //Measure Observation
    define function "Related ED Visit" (Encounter "Encounter" ) :
      Last(["Encounter" : "Emergency Department Visit"] ED
        where ED.status = 'finished'
          and ED.period ends 1 hour or less before start of Encounter.period
        sort by start of period )
Terminology
Code System | Description: Code system Diagnosis Role Resource: Diagnosis Role Canonical URL: `http://terminology.hl7.org/CodeSystem/diagnosis-role`
Value Set | Description: Value set Psychiatric/Mental Health Patient Resource: Psychiatric/Mental Health Diagnosis Canonical URL: `http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113883.3.117.1.7.1.299`
Value Set | Description: Value set Emergency Department Visit Resource: Emergency Department Visit Canonical URL: `http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113883.3.117.1.7.1.292`
Value Set | Description: Value set Hospital Settings Resource: Hospital Settings Canonical URL: `http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113762.1.4.1111.126`
Direct Reference Code | Display: Billing Code: billing System: `http://terminology.hl7.org/CodeSystem/diagnosis-role`
Dependencies
Dependency | Description: FHIR model information Resource: http://hl7.org/fhir/uv/cql/Library/FHIR-ModelInfo|4.0.1 Canonical URL: `http://hl7.org/fhir/uv/cql/Library/FHIR-ModelInfo|4.0.1`
Dependency | Description: Library FHIRHelpers Resource: http://hl7.org/fhir/uv/cql/Library/FHIRHelpers|4.0.1 Canonical URL: `http://hl7.org/fhir/uv/cql/Library/FHIRHelpers|4.0.1`
Data Requirements
Data Requirement | Type: Encounter Profile(s): Encounter Must Support Elements: period, use, rank, rank.value, condition, condition.reference
Data Requirement | Type: Encounter Profile(s): Encounter Must Support Elements: type, period, status, hospitalization, hospitalization.admitSource, use, rank, rank.value, condition, condition.reference Code Filter(s): Path: type ValueSet: Emergency Department Visit
Data Requirement | Type: Condition Profile(s): Condition Must Support Elements: id Code Filter(s): Path: id
Parameters
Name | Use | Card. | Type | Documentation
Measurement Period | In | 0..1 | Period |
Stratification 3 | Out | 0..* | Encounter |
Stratification 2 | Out | 0..* | Encounter |
Measure Population Exclusion | Out | 0..* | Encounter |
Stratification 1 | Out | 0..* | Encounter |
Initial Population | Out | 0..* | Encounter |
Measure Population | Out | 0..* | Encounter |
Generated using version 0.5.4 of the sample-content-ig Liquid templates