search "class" parameters don't seem to align with FHIR

[jmandel]

We define search classes as:

"Consult", "Discharge", "HandP"

... but FHIR (or at least their examples) doesn't use these convenient shorthand values

<class>
    <system value="http://ihe.net/xds/connectathon/classCodes"/>
    <code value="History and Physical"/>
    <display value="History and Physical"/>
  </class>

Is this a problem?

[jmandel]

Now class has been removed in FHIR; a DocumentReference has a type which is coded (LOINC recommended). Should we define a mapping from CCDA document types --> LOINC document ontology?

E.g. using the most-generic codes from C-CDA Docuement-level templates:

C-CDA Doc Type	Loinc Code	Notes
Continuity of Care Document	34133-9
Consultation Note	11488-4
Diagnostic Imaging Report	18748-4
Discharge summary	18842-5
History and Physical Note	34117-2
Operative Note	11504-8
Procedure Note	28570-0
Progress Note	11506-3
Unstructured document	34109-9	No code specified in C-CDA...
Lab report	11502-2	Not an official C-CDA document template...

[kwboone]

It looks as if classCode was replaced with category, which is exactly what it classCode did. classCode is a short list, typeCode a detailed list. Your short list above is probably right if we wanted to look at it from the LOINC and coding perspective, but what I did was use a smaller, easier to remember set of mnemonic codes that could be mapped to LOINC or to another coding system if need be.

[jmandel]

The new category is different from the old classCode in that it's a [separate patient-specific Resource](A patient-specific category) (not just an inline code). The example from FHIR is:

  <category>
    <type value="Category"/>
    <url value="../category/@1.2.36.90146595217.4.2.1"/>
  </category>

An example of a category is "Referrals for Patient 6578946".

[kwboone]

The Category search parameter is a qtoken on the DocumentReference resource, and so, I think we can use an inline code. It requires a discussion with the FHIR team (which I'll be able to have in just less than two weeks).

[jmandel]

Re: LOINC codes vs. short, user-friendly, readable codes: by all means I'm happy to go the short, friendly route. The reasons I switched to LOINC were:

1. Conform to the FHIR spec's requirements (or at least strong recommendations)
2. Match the document/code values specified in C-CDA

I had also assumed (incorrectly?) that these document/code elements would be the ones typically available from an XDS server. Otherwise: when does the XDS server assign the short, friendly type codes? Is there an official set of these in an XDS spec?

[kwboone]

We'd be a gateway. CCDA specifies multiple codes for document type, but our simple codes would translate into NWHIN Exchange query using all possible appropriate LOINC Codes whne using XCA, or internally translated for other mechanisms.

Keith

On Apr 24, 2013, at 3:33 PM, Josh Mandel notifications@github.com wrote:

Re: LOINC codes vs. short, user-friendly, readable codes: by all means I'm happy to go the short, friendly route. The reasons I switched to LOINC were:

Conform to the FHIR spec's requirements (or at least strong recommendations) Match the document/code values specified in C-CDA I had also assumed (incorrectly?) that these document/code elements would be the ones typically available from an XDS server. Otherwise: when does the XDS server assign the short, friendly type codes? Is there an official set of these in an XDS spec?

— Reply to this email directly or view it on GitHub.

[jmandel]

Great -- so I'll revert to your set of codes and we can assume some mapping step will happen server-side as needed.

C-CDA Doc Type	Loinc Code	Notes
Continuity of Care Document	Summary	Changed from @kwboone's "Summaries" to stay consistently singular
Consultation Note	Consult
Diagnostic Imaging Report	Imaging
Discharge summary	Discharge
History and Physical Note	HandP
Operative Note	Operative
Procedure Note	Procedure
Progress Note	Progress
Unstructured document	Unstructured	Added to @kwboone's set
Lab report	Lab	Not a C-CDA document template