I have a student who's parents refuse to allow any testing to be done (even though it's obvious that something needs to be done) because they "don't want to put a label on her." And they're "satisfied with her progress and think she is progressing with the curriculum just fine" (Their words). Mind you, she's over a year behind, and started a year late to boot.
What I would like to tell them is - why would you send your child to public school to, basically, disagree with everything that the professionals there tell you? If you know better than trained professionals, just homeschool then (which is VERY common here).
Honestly, it insults our profession, training, experience, etc. when that happens. We do everything in our power (sometimes even beyond) to help their children to be successful, but it's as if they would rather them not.