[Batman has just fought off Scarecrow and a group of Batman wannabes]
Batman: Don't let me find you out here again.
Brian: We're trying to help you!
Batman: I don't need help.
Dr. Jonathan Crane: Not my diagnosis!
Brian: What gives you the right? What's the difference between you and me?
[Batman lowers himself into the Batmobile]
Batman: I'm not wearing hockey pads!
-- The.Dark.Knight 2008
What's meant by Not my diagnosis in this context? I don't get it.