Using LOINC in HIPAA Attachments
LOINC helps providers and payers speak the same language.
The HIPAA Administrative Simplification provision mandates the adoption of standards for electronic claims attachments. A claims attachment includes the clinical and administrative information often necessary to adjudicate claims for ambulance, rehabilitation, or emergency room services. Regenstrief has worked closely with the HL7 Attachments Work Group to support the use of LOINC codes in the electronic exchanges of attachments between payers and providers.
The current proposed specifications for attachments use LOINC codes for three main purposes:
- To identify the specific kind of information being communicated in both a request and response (e.g., a discharge summary or diagnostic imaging report).
- To optionally specify certain modifier variables in fulfilling the request for information (e.g. variables that indicate a modification to the default time period).
- In structured attachment responses using HL7 CDA, LOINC codes identify the attachment (document) type, sections, and sometimes the individual entries (tests or observations).
There are 3 main ways to identify LOINC codes that can be used as valid attachment types.
In the LOINC Table
For Attachment Requestors (e.g. Payers)
The LOINC Table also contains a field called ValidHL7AttachmentRequest. A value of ‘Y’ in this field indicates that this LOINC code can be sent by a payer as part of an HL7 attachment request for additional information. The set of terms that can be used in requests for additional information include:
- The preferred (generic) document codes that have clinically-relevant HL7 implementation guides
- The HL7 AWG-approved document codes don't yet have an implementation guide
For Attachment Responders (e.g. Providers)
The LOINC Table (available for download in several file formats) contains a field called HL7_ATTACHMENT_STRUCTURE. For attachments approved by the HL7 AWG, this field will be populated with a value of “IG exists” (previously STRUCTURED) or “No IG exists” (previously UNSTRUCTURED) for relevant terms.
The “IG exists” terms are those that have clinically-relevant HL7 implementation guides that use the U.S. Realm Header. The “No IG exists” terms are those approved by the HL7 Attachments WG for transmission using the Unstructured Document template of the C-CDA.
For both requestors and responders looking for appropriate LOINC codes to use in attachments, that content can found easily in RELMA through a special form for browsing the attachment content. Just look for the HIPAA menu and you'll be on your way.
If you want, you can read more about how to browse the attachment content with RELMA here.
In RELMA, you can also find attachment content by searching on the HL7_ATTACHMENT_STRUCTURE field with RELMA's easy to use search syntax.
For example, to search for all the LOINC terms with value in HL7_ATTACHMENT_STRUCTURE of “No IG exists” containing the word “consent”, you could enter this query in the search box:
To find the set of progress note terms that could be used with the HL7 C-CDA implementation guide, you could search:
progress note HL7AttachmentStructure:IGexists
To search for all of the terms that can be used in attachment requests for additional information, you could enter this query:
Similarly, the attachment codes in LOINC can be easily located in the online LOINC search application, which uses is the same search syntax as that of RELMA. This powerful search syntax can search on keywords anywhere in the LOINC records or with a particular field.
For example, to search for all the LOINC terms with value in HL7_ATTACHMENT_STRUCTURE of “No IG exists” you could enter this query in the search box:
Actually, you can just follow this link to run the query above on search.loinc.org.
Similarly, to search for all of the terms that can be used in attachment requests for additional information, you could enter this query:
Or, you could follow this link to run the query above.
Similar to RELMA, the rows in the search results grid of the online search application can be highlighted and then exported to a CSV file.