It is sometimes necessary to add a new keyword to take into account different information in a newly encountered piece of text. This can create problems because the new keyword can appear in between existing ones, and so a derived pattern attribute may no longer find this new pattern of keywords.

For example, suppose that we decide that “close” is an important concept when applied to a family member, and needs to be a new keyword, e.g “CL”. A note such as anaemia, diabetes in close family, overweight” that previously corresponded to keywords “ANAEMIA DM FH” now becomes “ANAEMIA DM CL FH”. A derived pattern attribute FH_DB looking for “DM FH” would now not find it.

To help find these problems, the example text of each pattern of keywords is checked each time keywords are edited. If the derived pattern attribute no longer finds its pattern in the example text, the pattern is shown in red:

The pattern can then be edited to take into account the changed list of keywords. In the example above, you would add a new pattern “DM CL FH” for the derived pattern attribute FH_DB. As well, to correct the now-red pattern “DM FH”, you would need to change its example from “diabetes in close family” to “diabetes in family”.