When the ONC released the Standards and Certification NPRM, the companion to the CMS Meaningful Use Stage 2 NPRM, the new standard for the electronic transfer of Care Summary was defined as §170.205(a)(3) Consolidated CDA. CCD, along with CCR, was the standard for Stage 1 of Meaningful Use, and CCD is a constraint on CDA. So what does that make Consolidated CDA?
A draft Implementation Guide for CDA Release 2.0, Consolidated CDA Templates (U.S. Realm) was released in December 2011. A copy of the draft can be found on the HL7 web-site. HL7 defines the Consolidated CDA guide as “the single source for implementing the following CDA documents,” including Continuity of Care Document (CCD), discharge summary, and many others.
In the creation of the Consolidated CDA guide, HL7 reviewed the eight existing HL7 Health Story guides, CCD, and the additional constraints from IHE, HITSP and Stage 1 Meaningful Use. It is the scattering of all this documentation that led to the effort to create one guide that could be used for implementation and analysis of documents within the CDA standard. In creating the new single guide, HL7 aimed to eliminate conflicts among the previously scattered documentation and reduce ambiguity of the standard in general.
At the heart of the Consolidated CDA solution is a library of reusable CDA templates. As defined by Dr. Bob Dolin during his presentation on Consolidated CDA at the HL7 booth during HIMSS12, templates are critical to CDA for the following reasons:
- Templates lead to streamlined development by providing reusable building blocks.
- Templates provide quicker implementation because users can implement once, and deploy often.
- Since they are modular, templates (such as blood pressure, discharge diagnosis) can be repackaged with other templates in any number of CDA implementation guides.
- Templates provide for “incremental interoperability,” in that one can begin with simple CDA, and then add templates as they are prioritized.
Templates are also computable artifacts, which allow for easier machine-to-machine communication, and the transfer and storing of more data for clinical decision software.
Templates can be utilized at multiple levels within a CDA document:
- Level 1: Document Level Templates, such as CCD or Discharge Summary, can be utilized to define a template for the document as a whole.
- Level 2: Section Level Templates, such as Allergies or Medications, can be utilized to define what specific information will be included in each section.
- Level 3: Entry Level Templates, such as specific Observations or Procedures, can be utilized to define how the information is encoded within each section.
Templates are defined at all levels within the Consolidated CDA guide, which leads to incremental interoperability as more templates are incorporated into a document at progressing levels of interoperability from Level 1 to Level 3.
In general, the consolidation of the various implementation guides that existed for Stage 1, along with the new one-stop shop library for finding templates, should be a huge aid to implementers and providers alike who are attempting to understand the CDA standard. Removing conflicts and ambiguities will help with consistency among documents created from different sources.
Since Consolidated CDA has a document level template for CCD, I would assume that this template would be utilized for the Care Summary documents referred to when the ONC released the Standards and Certification NPRM. Aside from the cleaning up of conflicts and ambiguities, I would not expect this Consolidated CDA document to be much different from the CCD (C32) standard utilized in Stage 1.
Have you had any experiences working with the new Consolidated CDA standard? If so, please discuss in the comments below.