Clinical Statements
The article Clinical act statements, provides an overview of the clinical statements that form the “core” of a CDA document. Clinical statements are contained within entry elements, which in turn are contained within section elements, which in turn comprise the structured CDA Body, located in the XML path: ClinicalDocument/component/structuredBody.

Clinical statements begin with an XML element of: act, encounter, procedure, observation, substanceAdministration, supply, or organizer.

The article What goes inside a clinical statement XML entry?, overviews some of the sub-elements and attributes that all clinical act statements have in common.

“Procedure” Clinical Statements
In the underlying HL7 v3 model on which CDA is based, a “procedure” is defined as: An Act whose immediate and primary outcome (post-condition) is the alteration of the physical condition of the subject. It goes on to note that: taking an x-ray image may sometimes be called “procedure,” but it is not a Procedure in the RIM sense, for an x-ray image is not done to alter the physical condition of the body.

What Is Considered a “Procedure”?
As noted in the quote above, the term “procedure” is used informally to refer to things that are not formally considered a “procedure” in a CDA context (and thus, also, in a C-CDA context). It’s not always clear what constitutes an “alteration of the physical condition” and what doesn’t. An appendectomy would clearly be a “procedure”, but is the drawing of blood for a lab test a “procedure” or not? There is technically an “alteration” of the skin surface, the drawing of blood, etc. – yet at a high level the patient’s physical state is not altered by this activity. It’s also unclear if a “procedure” that alters “mental state” (such as counselling) meets that definition.

At the time of the writing of this revision of this article, there is significant sentiment among HL7 leaders that defining a “procedure” in terms of whether it results in an “altered state” is problematic – and there are discussions and plans about changing that definition in future versions of CDA and/or in future HL7 standards.

As a practical matter, the XML syntax of the procedure element (see below) can be a helpful guide. If there is a benefit/need in using the sub-elements noted below that are part of the procedure element and are not part of the act element, then the use of a procedure element is probably warranted.

If it is uncertain if a given “procedure” qualifies for representation via a CDA procedure element, the act element should be used.

classCode and moodCode Attributes of procedure
The classCode attribute of the procedure element is generally set to the value “PROC”. This is not a default value and must be set explicitly. In C-CDA templates that are applied to the procedure element, there typically is a declared rule that states that the value “PROC” must be assigned to the classCode attribute.

The moodCode attribute of the procedure element can take the same set of allowed values as the act clinical statement element. In other words, any of the allowed values for the moodCode attribute can be used, except for “GOL” (goal) and “EVN.CRT” (precondition). Refer to The moodCode attribute, for additional information.

Sub-Elements of procedure
For the most part, the procedure clinical statement element supports the same sub-elements as the act clinical statement element. This includes sub-elements used to express entry relationships (refer to Act relationship elements) and participations (refer to Participation elements). However, there are three sub-elements that are unique to procedure and help refine the information in the code sub-element that is common to all clinical act elements:

  • methodCode: Used with some code systems for expressing procedures to further qualify the procedure represented in the code sub-element of procedure.
  • approachSiteCode: Takes one of the SNOMED-CT codes for describing the parts of the body (from the relevant SNOMED-CT “code hierarchies” related to body structure). Represents the anatomical site or system through which the procedure reaches its target.
  • targetSiteCode: Takes the same set of allowed values as approachSiteCode. Represents the anatomical site or system that is the focus of the procedure.

Other CDA PRO Know Articles Referenced In This Article