[1] CDA specifies the syntax and supplies a framework for specifying the full semantics of a clinical document, defined by six characteristics:[2] CDA can hold any kind of clinical information that would be included in a patient's medical record; examples include:[1] 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.
[citation needed] 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.
[citation needed] In 2012, in response to conflicting CDAs in use by the healthcare industry, the Office of the National Coordinator for Health Information Technology (ONC) streamlined commonly used templates to create the Consolidated-CDA (C-CDA).
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.