As long as she can identify ROCKETS red, we should have no problems. Seriously, though... can't the doctors be the only ones to determine that? I hope every case is different as far as age at diagnosis, etc.
I know that the colors red & green have to do with colorblindedness(?) but my son often confuses yellow and red. Mostly just words, says one when he means the other. But he is 27 and really, really, really feckin' stupid. He also can't pronounce the word "colonial." Hope this helps.
Confusing just the words is a different sort of problem. It's not always a big deal but what happens is that two similar mental objects and their names get confused a few times which starts to set a mental path causing you to keep making the error verbally, often without realizing it until you hear yourself say it. As I understand it, it rarely happens with completely different items (apples and cars) just two closely related ones.
"Today, my five-year-old came home from summer camp crying because her friends and counselors had all laughed at her when she couldn't identify colors correctly during a game. My husband then confessed that he had taught her colors wrong because he thought it would be funny. FML"
It is my understanding that colour blindness in females is essentially non existent. This is a product of mankind's hunter-gatheror past. While the males went out and hunted animals, the females gathered barries, fruits and other plants. This forced the female to have a keener sense of colour indentification, in order to avoid failing her family by selecting poisonus plants.