When implementing an EHR system, or EHR module, that supports the Meaningful Use Stage 2 program for Clinical Quality Measure (CQM) support, there are three HL7 XML standards that you need to be aware of:
- HQMF
- QRDA Category 1
- QRDA Category 3
The HQMF XML standard defines the data elements referenced by the logic, and associates them to value sets using object identifiers (OIDs). For those really interested in using the HQMF, you can download the HQMF files for all the Meaningful Use Stage 2 Clinical Quality Measures from the CMS site here.
The QRDA Category 1 XML standard is what is used for expressing patient-level data as inputs to a Clinical Quality Measure calculator, such as popHealth, as part of the Meaningful Use Stage 2 program. This XML standard allows for EHRs to express the clinical results of individual patients based on the CQM that an EHR system was queried about. The reports that determine the data to include in the QRDA Category 1 XML are tightly coupled to the HQMF definition of the measure. I have shared high-level information about the QRDA Category 1 specification, as well as an example of what the QRDA Category 1 XML should look like.
Lastly, the QRDA Category 3 XML standard is what is used to express the summary results of a CQM. It is unfortunate that the QRDA Category 1 and Category 3 are worded so similarly, yet have significantly different roles in this landscape. The QRDA Category 3 is the artifact that needs to be generated for expressing summary/aggregate report numbers. For instance, if the CQM report where created to assess the mammography screening results of women between the ages of 45 and 65 years old, and the result were 73% of that population met that criteria, the QRDA Category 3 XML could express the 73% performance rate, as well as counts associated with the initial patient population, the denominator, the numerator , the exception, and exclusion populations. You can view an illustration of these different CQM logical families for the proportion-based CQMs here.
Below is an illustration that details the use of these various HL7 XML standards when reporting on Meaningful Use Stage 2 Clinical Quality Measures.
Landscape of Meaningful Use Stage 2 Clinical Quality Measure XML Standards |
Hopefully this is helpful. If not, let me know!
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. © Rob McCready, 2013.