The lcMatchingHeader element was deprecated in DITA version 1.3. It was replaced with the lcMatchingHeader2 element. It was originally intended to provide column headings for items to present in a matching table.
See appendix for information about this element in OASIS document type shells.
+ topic/sthead learningInteractionBase-d/sthead learning-d/lcMatchingHeader
... <lcMatchingHeader> <lcItem>Team</lcItem> <lcMatchingItem>City</lcMatchingItem> </lcMatchingHeader> ...