10.14 HL7v2 Hierarchic Designator Macro

Table 10-17 describes the attributes for identifying an entity (system, organization, agency, or department) that has responsibility for managing or assigning a defined set of instance identifiers (such as placer or filler number, patient identifiers, provider identifiers, etc.). This entity could be a particular health care application such as a registration system that assigns patient identifiers, a governmental entity such as a licensing authority that assigns professional identifiers or drivers' license numbers, or a facility where such identifiers are assigned.


This definition is identical to HL7 v2.5, Section 2.A.33, with only minor changes for editorial style.

These attributes are equivalent to the components of the HL7 v2 Hierarchic Designator (HD) and Entity Identifier (EI) data types (see HL7 v2 Chapter 2.A).

If both Local Namespace Entity ID (0040,0031) and Universal Entity ID (0040,0032) are present, they shall refer to the same entity.

Table 10-17. HL7v2 Hierarchic Designator Macro Attributes

Attribute Name



Attribute Description

Local Namespace Entity ID



Identifies an entity within the local namespace or domain. Required if Universal Entity ID (0040,0032) is not present; may be present otherwise.

Universal Entity ID



Universal or unique identifier for an entity. Required if Local Namespace Entity ID (0040,0031) is not present; may be present otherwise.

Universal Entity ID Type



Standard defining the format of the Universal Entity ID. Required if Universal Entity ID (0040,0032) is present.

Enumerated Values:


An Internet dotted name. Either in ASCII or as integers


An IEEE Extended Unique Identifier


An International Standards Organization Object Identifier


Uniform Resource Identifier


The DCE Universal Unique Identifier


An X.400 MHS identifier


An X.500 directory name