4.3.5 Section
Narrative
Block
The Section.text field is used to store narrative to be rendered, as
described above in CDA Conformance (§ 1.3 ), and is therefore referred to
as the CDA Narrative Block. The narrative schema defined for CDA R3 has
been aligned with a subset of the elements found in HTML, in order to
simplify content generation and presentation. One notable exception is the
continued reliance on <footnote> and <footnoteRef>, which are typically
not included in clinical notes, but were retained for backwards
comparability and continued support of SPL.
The CDA Narrative Block schema can be found here.
The content model of the CDA Narrative Block schema is specially hand
crafted to meet the requirements outlined above (see Human Readability
and Rendering CDA Documents (§ 1.2.3 )). The schema will be registered
as a MIME type (text/x-hl7-text+xml-r2), which is the fixed media type for
Section.text. Components of the schema are described in the sections that
follow.
4.3.5.1
<span> - content wrapping
The CDA <span> element is used to wrap a string of text so that it can be
explicitly referenced, or so that it can suggest rendering characteristics.
The <span> element can nest recursively, which enables wrapping a string
of plain text down to as small a chunk as desired.
The <span> element contains an optional identifier, that can serve as the
target of a reference. All values of attributes of type XML ID must be
unique within the document (per the W3C XML specification). The
originalText component of a RIM attribute present in any CDA entry can
make explicit reference to the identifier, thereby indicating the original text
associated with the attribute in the CDA entry.
Example 5
<section>
<code code="10153-2"
codeSystem="2.16.840.1.113883.6.1"
codeSystemName="LOINC"/>
<title>Past Medical History</title>
<text>
There is a history of <span id="a1">Asthma</span>
</text>
<entry>
<observation classCode="OBS" moodCode="EVN">
<code code="195967001"
codeSystem="2.16.840.1.113883.6.96"
codeSystemName="SNOMED CT"
displayName="Asthma">
<originalText>
<reference value="#a1"/>
</originalText>
</code>
<statusCode code="completed"/>
</observation>
</entry>
</section>
There is no requirement that CDA entries must reference into the CDA
Narrative Block. The referencing mechanism can be used where it is
important to represent the original text component of a coded CDA entry.
4.3.5.2
<a> - anchor element
The CDA <a> is a generic referencing mechanism, similar to the HTML
anchor tag. It can be used to reference identifiers that are either internal
or external to the document.
Multimedia that is integral to a document, and part of the attestable
content of the document requires the use of a supporting reference to an
ObservationMedia CDA entry, which is referenced by the <img> narrative
element (see <img> (§ 4.3.5.7 )).
Multimedia that is simply referenced by the document and not an integral
part of the attested document can use the <img> element without a
corresponding reference to an ObservationMedia or RegionOfInterest CDA
entry.
The source of a link uses the a.href attribute. The target of an internal
reference is an identifier of type XML ID, which can exist on other elements
in the same or a different narrative block, or XML ID attribute of type xs:ID
that have been added to the <section>, <ObservationMedia>, or any
narrative element of the CDA Narrative Schema providing an attribute of
type xs:ID. The use of the a.name attribute is deprecated, because
attributes of type XML ID provide an alternative and more consistent target
for referencing. Following the conventions of HTML, an internal link is
prefaced with the pound sign, as shown in the following example.
Example 6
<section ID="SECT001">
<code code="10164-2"
codeSystem="2.16.840.1.113883.6.1"
codeSystemName="LOINC"/>
<title>History of Present Illness</title>
<text>Mr. Smith is a 57 year old male presenting with
chest pain. He sustained a myocardial infarction 3
years
ago, ...
</text>
</section>
...
<section ID="SECT003">
<code code="10153-2"
codeSystem="2.16.840.1.113883.6.1"
codeSystemName="LOINC"/>
<title>Past Medical History</title>
<text>History of coronary artery disease, as noted
<a href="#SECT001">above</a>.</text>
</section>
CDA links do not convey shareable meaning. Shareable semantics are only
achieved by the inclusion of CDA entries and their associated formalized
relationships. There is no requirement that a receiver render an internal or
external anchor link, or the target of an external link.
4.3.5.3
<sub> and <sup> - superscript & subscript
The CDA <sub> and <sup> elements are used to indicate subscripts and
superscripts, respectively.
Receivers are required to interpret these elements when rendering by
visually distinguishing subscripted and superscripted characters.
4.3.5.4
<br> - line break
The CDA <br/> element is used to indicate a hard line break. It differs
from the CDA <paragraph> element in that the <br/> element has no
content. Receivers are required to interpret this element when rendering so
as to represent a line break.
4.3.5.5
<ins> and <del> - Deprecated
The CDA <ins> and <del> elements can be used to indicate narrative
changes from the last version of a CDA document. The usage of the
elements is limited to a single generation, in that it only reflects the
changes from the preceding version of a document. If applied, it needs to
be used in conjunction with standard CDA revision tracking. Changes to a
CDA document that has been released for patient care still require a formal
versioning and revision, and the revised document can optionally carry the
<ins> and / or <del> elements to show the delta in the narrative.
Receivers are required to interpret the <del> element when rendering by
visually distinguishing or suppressing deleted narrative.
We proposal to deprecate the use of <ins> and <del> with this revision, as
it is redundant with the normal versioning supported in the CDA header
using the relatedDocument / parentDocument elements.
4.3.5.6
<footnote> and <footnoteRef>
The CDA <footnote> element is used to indicate a footnote. The element
contains the footnote, inline with the flow of text to which it is applied.
The <footnoteRef> element can reference an existing footnote in the same
or different CDA Narrative Block of the same document. It can be used
when the same footnote is being used multiple times. The value of the
footnoteRef.IDREF must be an footnote.ID value in the same document.
Receivers are required to interpret these elements when rendering by
visually distinguishing footnoted text. The exact rendition is at the
discretion of the recipient, and might include a mark at the location of the
footnote with a hyperlink to the footnoted text, a simple demarcation (such
as "This is the text [this is the footnote] that is being footnoted"), etc.
Use Cases for footnote in clinical documents; have not been identified over
the course of the CDA R2. As a result, the use of <footnote> and
<footnoteRef> elements is deprecated in CDA R3.
Note: Implementation Guides are encouraged to prohibit the use of these
two elements in CDA R3 Implementation Guides, in order to simply the
processing requirements for narrative text.
4.3.5.7
<img> - multimedia references
The CDA <img> element is used to reference external multimedia. Direct
references to external multimedia using <img> are not assumed to be
integral to or attested in the document and maybe excluded in CDA
document exchanges. Multimedia that is integral to a document, and part
of the attestable content of the document, must therefore reference either
a contained ObservationMedia or RegionOfInterest entry to flag the
multimedia as attested and to show where the referenced multimedia is to
be rendered.
The <img> element contains a required src attribute (of type URI), the
value of which must equal the XML ID value(s) of ObservationMedia or
RegionOfInterest CDA entries within the same document when flagging the
content as authenticated and integral to the documents interpretation. The
<img> element also contains a required alt attribute that needs to specify
the alternate text for an image.
Example 7
<section>
<code code="8709-8"
codeSystem="2.16.840.1.113883.6.1"
codeSystemName="LOINC"/>
<title>Skin exam</title>
<text>Erythematous rash, palmar surface, left index
finger.<img src="#MM1" alt="image of:
left_hand_image.jpg" />
</text>
<entry>
<observationMedia classCode="OBS" moodCode="EVN"
ID="MM1">
<id root="2.16.840.1.113883.19.2.1"/>
<value xsi:type="ED" mediaType="image/jpeg">
<reference value="left_hand_image.jpeg"/>
</value>
</observationMedia>
</entry>
</section>
Multimedia that is simply referenced by the document and not an integral
part of the document can use <img>, but must not reference
observationMedia or RegionOfInterest elements.
The expected behavior is that the referenced multimedia should be
rendered or referenced at the point of reference. <img> elements can
either reference a single ObservationMedia, or a single RegionOfInterest.
In either case the multimedia should be rendered or referenced at the
point of reference in the narrative text.
If the <img> needs to reference more than one RegionOfInterest, each
RegionOfInterest must be a region on the same multimedia and contained
within a single Organizer element with a classCode =”GROUPER”. The
<img> will then reference the Organizer entry.
4.3.5.8
<p> - paragraphs
A CDA <p> is similar to the HTML paragraph, which allows blocks of
narrative to be broken up into logically consistent structures.
4.3.5.9
4.3.5.9.1
Various list types
<ol> - ordered lists
A CDA <ol> is similar to the HTML order list element. The <ol> element
will contain 1 or more <li> list item elements.
4.3.5.9.2
<ul> - unordered lists
A CDA <ul> is similar to the HTML unordered list element. The <ul>
element will contain 1 or more <li> list item elements.
4.3.5.9.3
<dl> - definition lists
A CDA <dl> is similar to the HTML definition list element. The <dl>
element will contain 1 or more <dt> definition items and/or <dd> item
definitions. Together these elements can be used to construct lists of terms
with definitions.
4.3.5.10
<table>
The CDA <table> is similar to the HTML table. The table markup is for
presentation purposes only and, unlike a database table, does not possess
meaningful field names.
CDA modifies the strict XHTML table model by setting the content model of
cells to be similar to the contents of other elements in the CDA Narrative
Block.
The table.border, table.cellspacing, and table.cellpadding attributes are
deprecated, because the styleCode attribute (see styleCode attribute (§
4.3.5.11 ) provides a more consistent way for senders to suggest
rendering characteristics.
4.3.5.11
<caption>
The CDA <caption> is a label for a table. Captions required for other CDA
narrative elements will need to be expressed as explicit narrative content
with the document. E.g. <p>Caption Text</p> any other narrative
element here.
4.3.5.12
style attribute
The style attribute is used within the CDA Narrative Block to give the
instance author the ability to suggest rendering characteristics of the
nested character data. Receivers are not required to render documents
using the styles provided and can present stylized text in accordance with
their local style conventions.
The CDA R3 style attribute values will be one or more cascading style sheet
properties = value pairs, separated by semicolons, similar to HTML. E.g.
style=”font-weight:bold;color:red” - for red bold text.
4.3.5.13
Other CDA Elements & Attributes
The remaining elements and attributes used are modeled after the XHTML
1.0 Strict Schema. Conformant implementations will only use the elements
listed below:
Element
a
br
caption
col
colgroup
dd
del
dl
dt
footnote
footnoteRef
img
ins
li
4.3.5.12
Usage
anchor
breakline
caption
column
column group
defintion
deleted
definition list
definition item
footnote
footnote reference
image reference
inserted
list item
Element
ol
p
span
sub
sup
table
tbody
td
tfoot
th
thead
tr
ul
Usage
ordered list
paragraph
span of content
subscript
superscript
table
table body
table data cell
table footer
table heading cell
table heading
table row
unordered list
Referencing in and out of the narrative block
NOTE: See entry (§ 4.3.4.2 ) for a discussion of the relationships between
a section and its contained entries.
To summarize the mechanisms for referencing in and out of the CDA
Narrative Block:




CDA entries can point in to the <span> element of the CDA Narrative
Block (see <span> - content wrapping (§ 4.3.5.1 )).
The <a> - anchor element of the CDA Narrative Block can reference
targets that are either internal or external to the document (see <a> anchor element (§ 4.3.5.2 )).
The <footnoteRef> element of the CDA Narrative Block can reference a
<footnote> element in the same or different CDA Narrative Block of the
same document (see <footnote> and <footnoteRef> (§ 4.3.5.6 )).
The <img> -multimedia references element of the CDA Narrative Block
can point out to CDA ObservationMedia and RegionOfInterest entries of
the same document (see <img> - multimedia references (§ 4.3.5.7 )).