Yes that's true. And OCD, ASD, etc. But ADD is supposed to be a diagnosis of elimination. If you haven't found something else to account for the symptoms, after all else has been looked at, you classify them ADD. In contrast, professionals with little to no experience with gifted or twice exceptional kids frequently leap to conclusions. ADD is one of those conclusions. You can be both gifted and ADD. You can also just be bright, bored to tears and annoying the fool out of the adults around you.