It is my understanding that ADD is really a misnomer, it's not about a deficit in attention - it's a decifict in cognitive control of attention. A poor ability to choose to pay attention to your doing your homework/taxes/other-boring-task (as compared to easily paying attention to reading a book, doing lego or playing monopoly), and also poor ability to switch attention.
I am pretty sure my 9yr old has ADD, my 5yr old might possibly have ADD (especially if it turns out her sister does), but I would say that there is a much higher chance she is your classic highly gifted kid with OEs.
