Clinical Document Architecture
 | This article relies largely or entirely on a single source. (August 2014) |
The HL7 Clinical Document Architecture (CDA) is an XML-based markup standard intended to specify the encoding, structure and semantics of clinical documents for exchange. CDA is an ANSI-certified standard from Health Level Seven International (HL7.org). Release 1.0 was published in November, 2000 and Release 2.0 was published with the HL7 2005 Normative Edition.
CDA specifies the syntax and supplies a framework for specifying the full semantics of a clinical document. It defines a clinical document as having the following six characteristics:
- Persistence
- Stewardship
- Potential for authentication
- Context
- Wholeness
- Human readability
A CDA can contain any type of clinical notes. Typical CDA document types include Discharge Summary, Imaging Report, History & Physical, and Pathology Report. An XML element in a CDA supports unstructured text, as well as links to composite documents encoded in pdf, docx, or rtf, as well as image formats like jpg and png.[1]
It was developed using the HL7 Development Framework (HDF) and it is based on the HL7 Reference Information Model (RIM) and the HL7 Version 3 Data Types.
The CDA specifies that the content of the document consists of a mandatory textual part (which ensures human interpretation of the document contents) and optional structured parts (for software processing). The structured part relies on coding systems (such as from SNOMED and LOINC) to represent concepts.
CDA Release 2 has been adopted as an ISO standard, ISO/HL7 27932:2009.[2]
Transport
The CDA standard doesn't specify how the documents should be transported. CDA documents can be transported using HL7 version 2 messages, HL7 version 3 messages, IHE protocols such as XDS, as well as by other mechanisms including: DICOM, MIME attachments to email, http or ftp.
Country specific notes
In the U.S. the CDA standard is probably best known as the basis for the Continuity of Care Document (CCD) specification, based on the data model as specified by ASTMs Continuity of Care Record. The U.S. Healthcare Information Technology Standards Panel has selected the CCD as one of its standards.
In the UK the ITK (Interoperability Toolkit) utilises the 'CDA R2 from HL7 V3 - for CDA profiles' for the Correspondence pack. See 'What standards does ITK utilise?' in the ITK FAQ.
In Australia the Personally Controlled Electronic Health Record(PCEHR) uses 'HL7 CDA format is used to transfer information between different healthcare clinical systems whilst still allowing information to be accessed and viewed'.
See also
- Health Level Seven International
- EHRcom
- Health Informatics Service Architecture (HISA)
- Continuity of Care Record
- Continuity of Care Document
- Gello Expression Language
- Fast Healthcare Interoperability Resources