Have you tried color coding? Perhaps you can make her additions another color so you'll get an instant feel for what's been added in your lists. It also sounds as though you don't want/or have time for the type of interaction where your assistant tells you what she has added to your workload. You want to be able to see it for yourself?
You could also have her summarize in an email whatever she's done, and set a rule to highlight that email (larger font, color, bold, whatever works) so you pull it up first thing and can get a handle on what's been happening.
I'm looking forward to everyone else's ideas on this as well. Thanks for asking!