Search Replace Transfer
The Workflow Filters feature is intended to make metadata entry more consistent and allow you to identify incomplete data or other problems.Run the menu command under Library > Plug-in Extras > Workflow Filters and the plugin adds a variety of fields to the Filter Panel or Smart Collections:
All of these extra audit fields can be shown in the Filter Panel (below) or in Smart Collections. Here in the Library Filter Panel, #Keywords shows me that 2 images have no keywords assigned, while most others have 6-10 or 11-15. So those 2 images probably need more attention.
Note that these are not “live” values - they are recalculated each time you run the Parse and Audut menu command. So, while Lightroom’s Smart Collections have a “keywords is empty” criterion, the pictures disappear as soon as you enter one keyword. With Workflow Filters, this doesn't happen as it only recalculates the number when you want it to. You can then see if you’ve entered as many keywords as you need - and identify any exceptions.
Parse fields 1-5
You can define up to 5 fields to audit, so you can filter by almost any field including EXIF, IPTC or Develop values. As with fields such as Title* or Caption*, these are recalculated each time you run the Parse and Audut menu command.