X.4.1 Equivalence

The CDA Document shall contain clinical content equivalent to the SR Document.

Note: The HL7 CDA standard specifically addresses transformation of documents from a non-CDA format. The requirement in the CDA specification is: “A proper transformation must ensure that the human readable clinical content of the report is not impacted.”

There is no requirement that the transform or transcoding between DICOM SR and HL7 CDA be reversible. In particular, some attributes of the DICOM Patient, Study, and Series IEs have no corresponding standard encoding in the HL7 CDA Header, and vice versa. Such data elements, if transcoded, may need to be encoded in “local markup” (in HL7 CDA) or private data elements (in DICOM SR) in an implementation-dependent manner; and some such data elements may not be transcoded at all. It is a responsibility of the transforming application to ensure clinical equivalence.

Many attributes of the SR Document General Module can be transcoded to CDA Header participations or related acts.