Components: <identifier (ST)> ^ <text (ST)> ^ <name of coding system (ST)> ^ <alternate identifier (ST)> ^ <alternate text (ST)> ^ <name of alternate coding system (ST)>
Example:
|F-11380^CREATENINE^I9^2148-5^CREATENINE^LN|
This data type transmits codes and the text associated with the code. To allow all six components of a CE data type to be valued, the maximum length of this data type must be at least 60 (see Section 2.6.2, "Maximum length").
Sequence of characters (the code) that uniquely identifies the item being referenced by the <text>. Different coding schemes will have different elements here.
Name or description of the item in question. E.g., myocardial infarction or X-ray impression. Its data type is string (ST).
Each coding system is assigned a unique identifier. This component will serve to identify the coding scheme being used in the identifier component. The combination of the identifier and name of coding system components will be a unique code for a data item Each system has a unique identifier. ASTM E1238-94,Diagnostic, procedure, observation, drug ID, and health outcomes coding systems are identified in the tables in Section 7.1.4, "Coding schemes". Others may be added as needed. When an HL7 table is used for a CE data type, the name of coding system component is defined as HL7nnnn where nnnn is the HL7 table number.
These three components are defined analogously to the above for the alternate or local coding system. If the Alternate Text component is absent, and the Alternate Identifier is present, the Alternate Text will be taken to be the same as the Text component. If the Alternate Coding System component is absent, it will be taken to mean the locally defined system.
Note: The presence of two sets of equivalent codes in this data type is semantically different from a repetition of a CE-type field. With repetition, several distinct codes (with distinct meanings) may be transmitted. |
Note: For HL7-defined tables which have not been adopted from some existing standard, the third component, "name of coding system" is constructed by appending the table number to the string "HL7". Thus, the field RXR-2-site, is a CE data type which refers to HL7 table number 0163. Its "name of coding system" component is "HL70163". |
Figures 7-2 and 7-3 list many diagnostic, procedure, observation, drug, and health outcomes coding systems. Guidelines for their use are presented in Chapter 7, Section 7.1, "Introduction and Overview."