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Wednesday, June 18, 2008

If I had a Hammer

“If the only tool you have is a hammer, you tend to see every problem as a nail.” — Abraham Maslow (1908-70), American psychologist

Recently, I ran across a question on the ANSI/HITSP C32 specification from an implementer. The C32 specification describes how the US Federal Government expects to use the HL7 Continuity of Care Document in our National Health Information Network.

The basic question we started with is how does one represent an operative report, a discharge summary, or a progress note in a C32 document.

I am still a bit confused with the 2 sections and what goes into each one, and the fact that we can't capture the document type (i.e., operative report vs. discharge summary vs. progress note).

The question expresses two parts of the problem:
  1. How do we make use of the CCD to create a uniform way to exchange information, and having done so,
  2. How do we classify documents as to the type of service they describe.
Fortunately, during the development of the CCD, the HL7 Structured Documents work group realized that the CCD templates for problems, medications, allergies, et cetera, could be reused in any other document built on the HL7 CDA standard. Realizing that, they created template identifiers that would allow these templates to be used in any kind of document.

Much work has been done on creating CDA documents using these CCD templates, in HL7, IHE and elsewhere. To date, there are implementations guides that have been developed by IHE and HL7 for:

Each of these implementation guides is using templates from the HL7 Continuity of Care Document, so that as we look inside each document, problems, medications, allergies and other clinical information have a uniform representation based on the CCD.

So the real question is not, "how to I put an operative note into a CCD", but rather,

How do we use the CCD specifications to record this information inside a _____(fill in the blank)?

The answer is to use the same templates created for the CCD, and in the ANSI/HITSP C32 specification in those other clinical documents.

The reason for doing this can be explained very simply. Imagine that you are a physician caring for a patient, and you want to find a particular document. It may be an operative note, a discharge summary, a consultation, et cetera. If all documents are CCD's, then you no longer have the capability to distinguish between them by the kind of service represented in the document. Can you imaging wading through all of these CCD's to find the right document? What you really want is for those documents to be classified by the kind of service performed by the provider. If it's a discharge summary, then it should say so.

Recently, the ANSI/HITSP Care Management and Health Records Technical Committee met in Washington DC, and discussed this topic. The solution proposed was to recognize that the C32 specifications applied not to just CCD documents, but to all HITSP created CDA based specifications. That committee will be reworking the HITSP specifications this year to better enable reuse of the C32 specifications across all clinical documents.

The HL7 Structured Documents work group will also be reviewing plans for development of the next release of the HL7 Continuity of Care Document later this year. The expectation is that we would propose changes based on feedback from implementers such as the NHIN implementation projects. When that work begins, I will be proposing a change to the very first conformance statement in the Continuity of Care Document. That statement is reproduced here:

CONF-1: The value for “ClinicalDocument / code” SHALL be “34133-9” “Summarization of episode note” 2.16.840.1.113883.6.1 LOINC STATIC.

My proposal will change this conformance statement to allow for the use of other LOINC codes when the purpose of the document is to contain a medical summary and documentation of other care. I've shown the proposed text below. Please note, this is only my proposal, there is no guarantee that this will become part of the next version of CCD, but it could help to address the confusion raised by the current specification.

CONF-1: A document conforming the these specifications may use any LOINC code in “ClinicalDocument / code” to describe its content. When the purpose of the document is solely to summarize the patient's current health status, the value for “ClinicalDocument / code” SHALL be “34133-9” “Summarization of episode note” 2.16.840.1.113883.6.1 LOINC STATIC.

We need use the right tool for the job, and while the CCD Document is a hammer, the CCD specification itself provides us with a whole box of tools -- CDA sections and entries. We can use these tools to build any number of clinical documents. Furthermore, having done so, we can expect that healthcare applications will be able to understand the content.