> News > NCPDP News > Did You Know? Association Between NCPDP Standards Versions and Applicable Data Dictionary Versions
Only one publication of the Data Dictionary is applicable to a version of a standard.
When utilizing the Data Dictionary, it is important to refer to the Standards Matrix (available in the Additional Information documents of the web-enabled Data Dictionary) to identify the applicable publication date/version of the Data Dictionary for the specific version of a Standard you are researching.
Whereas, the External Code List (ECL) can be applied to a version of a standard starting with the date of approval/release and all future publications of the ECL can also be used unless specifically noted by data element or value limitations within each ECL publication.
For example, for Telecommunication Standard Version D.0, the associated version of the Data Dictionary is July 2007. No earlier or later Data Dictionary publications are relevant. (Note: This version of the Data Dictionary is not web-enabled but remains available in PDF in the Standards Lookup on the NCPDP website). The July 2007 and subsequent versions of the ECL may be used for Telecommunication Standard Version D.0.