HL7 OID Registry Frequently Asked Questions

I already have an OID, does HL7 have to assign a new one?

No. There are two separate operations, the creation of an OID under the HL7 root, and the registration of an OID. When you select “Internal” on the form data entry page, HL7 will create an OID under the HL7 root and register it. If you select “External” on that page, you must enter the literal numeric form (dots and numbers) of the OID you already have, which will then be registered.

I have no idea what Type I should select for my OID

HL7 has created a Type ontology for the OIDs in the HL7 registry to make it easier for the user community to search for OIDs they may be looking for; this type has nothing to do with ISO standards, or any intrinsic meaning or form of the OID itself. It is only a convenience for the users of this Registry.

The following Types have been defined for use in the HL7 OID Registry:

• Type 1

HL7 registered internal objects (other than published documents and organizational bodies)

Type 1 OIDs are only used for certain internal administrative functions at this time.

• Type 2

HL7 organizational bodies and groups

Type 2 OIDs are only used to identify an HL7 Group, such as a Working Group, or an International Council Member of HL7, such as HL7 Australia.

• Type 3

External group functioning as a Registration Authority

Type 3 OIDs are used for organizations that wish to create their own trees of OIDs for their use. If you will be assigning OIDs yourself under the OID that you are applying for, then you should select Type 3. This effectively delegates Registration Authority to your organization for all OIDs under this new Type 3 OID. No one else anywhere will create OIDs under your new root. Every OID created ‘under’ this new root will be considered by HL7 to be an ‘external’ OID, since you will have created it external to the HL7 OID Registry OID assignment software. These may be requested or registered by anyone.