I used to do a lot of interviewing when I was a manager and I found that by talking to people for awhile about a system, job duties, whatever, I could get a good feel for whether they did or didn't know about it. A lot of people are full of it on their resume, that's for sure, lol.
One thing I always asked people...describe a typical day/job duties at your current (or most recent) job. What did you work on, what systems did you use, what reporting do you handle, what's your workday like?
Well if someone can't answer that, not a good result.
If they say they're an expert at system XYZ I ask them how they used the software, what tasks did they do, what do they think about the blah blah user functions, the blah blah reports, how did they sort their data in the system, etc. And we used Microsoft testing for their systems for admin, IT and call center reps.