has value of more recently is used to compare the times at which two attributes have attained a particular value (e.g. “true”).
A potential use of this is as follows. Suppose that Text Attributes ‘OnWarfarin’ and ‘OnHeparin’ had been set up to determine, from the clinical notes, whether a patient was on Warfarin or Heparin. Then this function could be used to see which of these drugs a patient was most recently using. For example, given the following case fragment:
01 Jun 03 20 Jun 03 03 Sep 03 15 Oct 03 02 Nov 03 GHI y b2 a1 x List1 false false true false false List2 false true false false false
List1 has value of “true” more recently than List2