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["Laboratory Test, Performed": "LDL-c"]

Performance/Reporting Period
Value Set Description from VSAC
Clinical Focus: This value set contains concepts that represent lab tests commonly used for low-density lipoproteins (LDL) cholesterol measurement.
Data Element Scope: This value set may use the Quality Data Model (QDM) category related to Laboratory Test. The intent of this data element is to identify patients who had a lab test on a source of serum or plasma.
Inclusion Criteria: Includes only relevant concepts associated with LDL-C tests using the source of serum or plasma based on a measurement scale of mass per volume.
Exclusion Criteria: No exclusions.

Constrained to codes in the Laboratory Test, Performed: LDL-c value set (2.16.840.1.113883.

QDM Datatype and Definition (QDM Version 5.4)

"Laboratory Test, Performed"

Data elements that meet criteria using this datatype should document the laboratory test indicated by the QDM category and its corresponding value set was performed.

A QDM Known Issue has been identified related to this datatype. To see this QDM known Issue, please click here.

Timing: The Relevant Period addresses:

  • startTime – when the laboratory test is initiated (i.e., the time the specimen collection begins)
  • stopTime – when the laboratory test is completed (i.e., the time the specimen collection ends)


  • Initiation of a venipuncture for a fasting blood glucose to the time venipuncture for the fasting blood glucose is completed – basically a single point in time for many specimen collections
  • Initiation of a 24-hour urine collection for measured creatinine clearance until completion of the 24-hour urine collection

Note – the time that the result report is available is a separate attribute than the time of the study (specimen collection).

QDM Attributes


Relevant Period addresses the time between the start of an action to the end of an action. Each datatype using relevant period defines specific definitions for the start and stop time for the action listed.


The final consequences or data collected from the datatype. Results can be used in four ways, to express: (1) That a result is present in the electronic record but any entry is acceptable. (2) A numerical result is reported directly as a value. Values may be integers or decimal numbers without units, or as a quantity with a value and units. Examples: 100 mg/dL for a lab test, 140 mmHg for blood pressure, as a percentage (actually a quantity with % as units), as a ratio (e.g., 1:4, 1:80). (3) A result that matches one of a specific set of coded concepts in a value set or a code that matches a direct reference code. (4) A result as a dateTime (Assessment, Performed and components). Note: Measures use Clinical Quality Language (CQL) logic to express the mathematical operators to constrain desired results to those above or below a certain threshold.


The time the result report is generated and saved in the database.

NOTE: Although 2020 eCQMs use QDM Version 5.4, the QDM Version 5.5 Guidance Update provides clarification to the definition of this attribute which may be helpful when implementing eCQMs for 2020 Reporting/Performance periods.

QDM Version 5.5 Guidance Update:
The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified.

Last Updated: Jul 08, 2021