I work on the IT side of a small health insurance related company. We don't directly do insurance, but we process claims for other insurers. One of the services we offer (that I don't work with, so I know little about) is claim auditing. We have folks that go to hospitals and audit claims to make sure everything on the bill is valid. They'll compare the notes in the charts to what's on the bill. Did you really get X days of a drug or was did discontinued after X-2 days? It's humans that enter the data in to the systems, and humans make mistakes, so we try to track down those mistakes to save money. I have no idea how they decide what claims to audit like that, but maybe it's worth asking your insurance company if they can order something like that. Just like, "hey, a lot stuff happened during that week, and we're not experts in what all these codes mean, do you guys have someone that can audit the bill to make sure everything looks right?"

I was just Googling around for something to give you info on it and found this site that sounds like the service we perform: http://www.medicalclaimshelp.org/medical_bill_auditing0.aspx