caBIG™ UML model. This is an example of a portion of a UML model of a system available in caBIG™. The model describes the classes and attributes of the system and information about function and relationships. Note the class Race has attributes id (a string identifier of a race) and raceDesc (a string description of a race). This Race class is mapped to a CDE within caBIG™ to give a semantic definition and allow reuse of this type of data element.