Unified Medical Language System® (UMLS®) Basics

Lexical Variant Generation (LVG)

The Lexical Variant Generation program contains a series of commands that can be selected and combined to perform lexical transformations to text. A variety of commands are available to process lexical variations such as:

• Inflections and conjugations
• Word order in multi-word terms
• Alphabetic case
• Punctuation
• Possessives

Users can create their own sequence of commands to process text to meet the needs of their applications. The Norm program is a predefined set of commands from the LVG program packaged together.