HL7 V3 Organization identifier to URN:OID

Question

I need to transform an HL7 V3 Organization identifier (root+extension) to an URN.

Organization id is as follows:

<Organization xmlns="urn:hl7-org:v3">
    <id>
        <item root="2.16.840.1.113883.4.2" extensions="26879954"/>
    </id> 

... As fas as I know I can use "URN:OID:2.16.840.1.113883.4.2"

But how to add extension value?

Thanks

Answer 1

You probably cannot. Organization <id> is the Instance Identifier (II) data type. The II data type identifies the root as “a unique identifier that guarantees the global uniqueness of the instance identifier. The root alone may be the entire instance identifier” and the extension as “a character string as a unique identifier within the scope of the identifier root”. In it turns, the root “must be a valid OID, UUID, or HL7 reserved identifier” so you cannot put an URN.

As an option, you may register your own OIDs as following - 2.16.840.1.113883.4.2.26879954 – in this case you need to keep a reference table to uniquely identify organizations.

The difference between these two is that in the fist case you identify a scoping authority and the organization within that authority. In the second case you identify an organization as a separate unique entity which does not belong to any scoping sets.

See HL7v3 Normative Edition for details.

Answer 2

I've been reviewing HL7 CCDA documentation! , and I see some HL7 CCDA templates expressed as: urn:hl7ii:2.16.840.1.113883.10.20.22.1.10:2014-06-09

So I guess the right way to represent an HL7 V3 id as URN:OID is: urn:hl7ii:{root}:{extension}