In the coding pattern, which element identifies the coding system?

In the coding pattern, which element identifies the coding system?

• A. System
• B. Version
• C. Display
• D. Code

Answer: (A)

In a Coding, the element that identifies the coding system is the system field. It holds the URI of the code system (for example, http://loinc.org or http://snomed.info/sct), which tells you exactly which vocabulary the code belongs to. The version field is separate and denotes the version of that code system, which matters when codes can change across releases. The code field is the actual code value within that system, and the display field is a human-friendly name for that code. For example, system: "http://loinc.org" with a code like "2345-7" identifies a specific LOINC concept, while the display might read "Glucose [Mass/volume] in Serum or Plasma." If the system weren’t specified, the same code value could refer to different concepts in different code systems, so identifying the system is essential.

In a Coding, the element that identifies the coding system is the system field. It holds the URI of the code system (for example, http://loinc.org or http://snomed.info/sct), which tells you exactly which vocabulary the code belongs to. The version field is separate and denotes the version of that code system, which matters when codes can change across releases. The code field is the actual code value within that system, and the display field is a human-friendly name for that code. For example, system: "http://loinc.org" with a code like "2345-7" identifies a specific LOINC concept, while the display might read "Glucose [Mass/volume] in Serum or Plasma." If the system weren’t specified, the same code value could refer to different concepts in different code systems, so identifying the system is essential.