HL7 CDA Progress Notes mapping LOINC Codes to HL7 sections

Question

I was looking at the document "HL7 Implementation Guide for Clinical Document Architecture, Release 2: Progress Note, Release 1" and it contains LOINC Codes for each section. For example, 51848-0 is the code for Assessment. How can I find out which HL7 segment does this maps to?

Answer 1

Not sure if this is what you are asking - look at page 24

CONF-PRGN-18: When the Assessment and Plan are recorded separately, there SHALL be a section where the value for section/code SHALL be 51848-0 ASSESSMENT 2.16.840.1.113883.6.1 LOINC

The CDA element is 'section/code' - the path down to that point is something like

ClinicalDocument/component/structuredBody/component/section/code

All those section LOINC codes map down to a specific 'section' element in the document body and set the 'code' element so you know what the section is about.

e.g

<section>
  ...
  <code codeSystem="2.16.840.1.113883.6.1" codeSystemName="LOINC"
code="51847-2" displayName="ASSESSMENT AND PLAN"/>
  ...
</section>

Spec states must have a section "ASSESSMENT AND PLAN" or two separate sections "PLAN OF TREATMENT" and "ASSESSMENT"

The example in the package helps a lot ans shows "ASSESSMENT AND PLAN" section in use..

Answer 2

LOINC codes are most often mapped to OBR or OBX segments depending on what the message is doing.

http://loinc.org/faq/getting-started/loinc-and-other-standards/

Answer 3

There is no direct map between HL7 v3 (CDA) and HL7 v2.x (messages and segments).

CDA Section information might be mapped to OBX segments in some cases, and if the LOINC code corresponds to a type of observation, you can put it in OBX-3: Observation Identifier, and the correspondent value should be on OBX-5: Observation Value.

Just for reference: http://hl7api.sourceforge.net/v25/apidocs/ca/uhn/hl7v2/model/v25/segment/OBX.html