Identifiers within a CDA document are of paramount importance, as they are used to track the document, section, and entries as they are management within the OpenSHR data model. OpenSHR will always assign identifiers to any piece of data contained within its data store and will share these identifiers via any on-demand document exported.
Implementers (content creators and consumers) are expected to maintain at least one of the identifiers provided to them for each piece of data that they convey to the SHR. If OpenSHR does not receive an identifier for a piece of data then it will always result in a "create" operation (i.e. it is impossible to update data without an identifier).
Identifiers are expressed using the II data type and can be represented in one of several ways illustrated in Table 1.
Table 1 - Representation of identifiers
Identifier |
Semantic Meaning |
<id root="1.3.6.1.4.1.19376.1.5.3.1.4.13.7"/> |
The identifier is globally unique based on the OID provided in the "root" attribute. |
<id root="1.2.3.4.5.6.9.100.1" |
The identifier 2-2014102895457 is unique within the identity domain 1.2.3.4.5.6.9.100.1. |
<id root="fcab9618-943d-4368-a0f6-4d27727889af"/> |
The identifier <uuid> is globally unique, or had no identifier/domain and a random identifier was assigned |
The preferred method of representing identifiers is using the root/extension method as it more easily identifies the domain which assigned the identifier. For example, a content creator may have a "patients" table with an incrementing primary key. It would be possible for that content creator to assign an OID to the "patients" table and use the primary key as the extension of that identifier.