What does it mean when a discrepancy's category includes "TMS"?

If your study is set up to use Oracle Thesaurus Management System (TMS) for coding source data to standard terminologies, or dictionaries, TMS processes designated data items with new or changed data during DMW transformation. If TMS is able to automatically code a designated source term to a dictionary term, it does so and derives specified data back to DMW.

TMS creates a discrepancy when it cannot automatically code a data item to a dictionary term.