Are click-throughs always real?

We've noticed click throughs that seem unexpected; like clients who aren't generally otherwise engaged. Or, report says that ALL the people at one organization seem to have clicked through. Are there other reasons why a click-through might be recorded when someone didn't actually click through themselves? Do email programs open and test the clicks before presenting an email to the recipient? How can we getter a better idea of who REALLY clicked on a link and is thus a more engaged prospect? Any tips or insight?