The code identifying the version of the READ CLASSIFICATION used.
Classification:
| a. | Read Code 4Byte Version (retired 1 October 2009) | 
| b. | Read Code Version 2 | 
| c. | Read Code Clinical Terms Version 3 (CTV3) | 
This attribute is also known by these names:
| Context | Alias | 
|---|---|
| plural | READ VERSIONS | 

