Source:http://linkedlifedata.com/resource/umls/id/C1554124
HL7V3.0: <p>New type. This row starts the definition of a new message element type. The subordinate rows beneath it compose the definition of the type. Each of these subordinate rows has the name of the message element type being defined in the In Message Element Type column. That name will be the same one that is in the Of Message Element Type of this row.</p>