[kurto]

There's actually a lot you can factor in to help... if you've been overly active even passive players will sometimes play back at you with hands weaker then your overpair. I know when I'm in this position I take into account recent activity in making my decision as to whether or not I think he's playing back light.

In general, I agree that these players often call down with simple one pair hands and draws. Though some will surprise you by unexpectedly playing their draws aggressively.

Note - these players are also the type to smoothcall a hand like QQ or AA and then raise you on the flop....

At any rate, its likely going to cost you two more streets of betting to find out if you're good. If you feel confident that a draw is most likely out of the question, then sets and two pairs are your most likely candidates and you can fold.