CMS FHIR Quality Measure Development IG
0.8.0-cibuild - CI Build
CMS FHIR Quality Measure Development IG
0.8.0-cibuild - CI Build
CMS FHIR Quality Measure Development IG, published by Centers for Medicare & Medicaid Services (CMS). This guide is not an authorized publication; it is the continuous build for version 0.8.0-cibuild built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/cqframework/cms-qmd/ and changes regularly. See the Directory of published versions
FHIR defines the AllergyIntolerance resource to represent allergies and intolerances for a patient. US Quality Core defines the US Quality Core AllergyIntolerance profile, which derives from US Core AllergyIntolerance, requires patient, and adds the resolutionAge extension.
Authoring patterns for allergies and intolerances are documented in AllergyIntolerance in the US CQL implementation guide, covering onset and abatement, along with worked examples for contrast dye, egg, and nut allergies. This page records only what differs for quality measurement; see the Pattern Index for the full list of available patterns.
For AllergyIntolerance, see also modifier elements, search parameters, and cross-version considerations in that guide.
NOTE: Retrieves in the US CQL patterns are written against the US Core model (
[USCore.AllergyIntolerance]). In CMS dQMs they are written against US Quality Core ([USQualityCore.AllergyIntolerance]). The element-level guidance is otherwise the same. The shared definitions in USCoreElements —All Allergies and Intolerances,Active Confirmed Allergies and Intolerances, and their variants — retrieve US Core-conformant instances, so measures requiring US Quality Core conformance should retrieve against US Quality Core directly.
NOTE: In addition, some systems capture “noted”, as when the allergy/intolerance was first noted. An extension has been proposed to capture this information: https://jira.hl7.org/browse/FHIR-59668
See Current allergies.
Quality measures are evaluated retrospectively, against the data that exists at the time of evaluation rather than during the measurement period. Because isActive() tests the current clinicalStatus, it may not be able to be used to establish that an allergy was active during the measurement period. See Onset, abatement, and prevalence period below.
See Onset, abatement, and prevalence interval.
abatementInterval() and prevalenceInterval() are defined in FHIRCommon; they were previously in QICoreCommon. For AllergyIntolerance, abatementInterval() accounts for the resolutionAge extension as well as abatement. prevalenceInterval() returns the interval from onset to abatement, closed at the end when the allergy/intolerance is active (a clinicalStatus of active) and open otherwise. Because isActive() tests the current clinicalStatus, the prevalence interval is the more reliable way to determine historical status when onset and abatement are available.
However, if onset, abatement, or resolution are not available, which is often the case for allergy/intolerance information, measures can fall back to the assertedDate, and failing that, the recordedDate elements as an approximation of active status (see Allergy date and relevant period). Alternatively, for allergy/intolerances that are not expected to abate, the use of clinicalStatus and verificationStatus directly may be the most reliable indicators.
KNOWN ISSUE: There is a known issue with the
prevalenceIntervalfunction for AllergyIntolerance; strongly consider the use ofprevalencePeriodin CQMConcepts 0.4.000. See Prevalence Interval Issue.
Similar to the condition resource, given that many systems do not track onset and abatement information for an allergy/intolerance, clinicalStatus may be the most reliable indicator, even for historical purposes (assuming the allergy/intolerance is not expected to abate). However, to support consistent handling and allow for usage of data if it is available, CQMConcepts 0.4.000 defines a relevantDate() function for AllergyIntolerance that returns the first available of:
Using this definition of relevantDate(), CQMConcepts also defines relevantPeriod(), analogous to prevalencePeriod(), but starting with the relevantDate(), rather than the onset. relevantPeriod() can be substituted wherever prevalencePeriod() is currently used, noting that:
prevalencePeriod() is used when logic should only consider clinically recorded onset when determining whether an allergy/intolerance is presentrelevantPeriod() is used when logic should preferentially consider clinically recorded onset, but fallback to assertedDate, and then recordedDate as the starting pointdefine "Egg Allergy During Measurement Period":
[USQualityCore.AllergyIntolerance: "Egg Allergen"] EggAllergy
where EggAllergy.isVerified()
and EggAllergy.relevantPeriod() overlaps "Measurement Period"
Note the following about the boundaries of both functions:
prevalencePeriod(); no onset, asserted, or recorded date for relevantPeriod()) has a closed null starting boundary, so it is treated as present from the beginning of time.isActive(), which is false when clinicalStatus is missing. An allergy/intolerance with no abatement then has an unknown (open null) ending boundary, so comparisons such as overlaps "Measurement Period" may return null rather than true.See No known allergies.
USCoreElements distinguishes No Known Allergies (Confirmed) from No Known Allergies (Not Asked); a measure asserting that a patient has no known allergies should use the confirmed form. Both definitions test isActive(), so the retrospective consideration above applies to them.
See Clinical and verification status.
Measure logic should use the verification-status functions defined in FHIRCommon — isVerified() and verified(), along with isConfirmed(), isUnconfirmed(), isRefuted(), and their list-valued forms — rather than re-declaring them locally. QICoreCommon’s verified() is deprecated in favor of the FHIRCommon function; see the Refactored Index.