Visual dyslexia only affects about 10% of dyslexics as the primary cause of their reading problems and so it is seldom the first thought about what intervention is needed. While that is as it should be , I don't think that it should only be considered after spending much time and money on interventions and concluding that the final results fall below what could be reasonably expected from those interventions.
To muddle things up more, there are perhaps another 20% of dyslexics who co-mingle visual and more prevalent language and auditory processing problems. As these dyslexics show the typical early speech and communication problems so common to dyslexia they are likely to be enrolled in whatever the local community has deemed the answer to dyslexia without visual problems ever being considered.
People tend to believe their own senses and assume whatever they experience is normal. This is particularly true in children. Depending on the age of the child, visual problems can sometimes be determined by discussions about their vision. Being extremely near sighted all my life my Ah-ha moment came when I went to school with my first pair of glasses. I found that my teacher was not doing her usual arm waving dance up front while explaining things by the black board but was actually writing on the black board. I had no idea . It occurred to me later that if someone had asked how well I could read the blackboard I would have answered " read what?". I also remember my first eye exam and the first question . What direction is the E pointing? my answer " what E ?". My mother almost screamed THAT E ON THE WALL , "what E? I said.
My point being that , at least for me , as a child I thought my vision was normal . My fuzzy little world where only things closer than my outstretched arm were clear was normal. Later in life I realized that any discussion about my vision would have revealed its flaws.
My criteria for whether the See Right Dyslexia Glasses will help visual dyslexics is: can the visual dyslexic describe specific visual problems that make reading difficult. That works well for adults. Children can often answer questions about how they see the page that indicate problems that to them seems normal. Are all the words clear ,sharp , in focus , stable or in motion, and look uniform?
I am going to add another indication of visual dyslexia for children that parents can check. It is not universal but often can be used as an indication of visual dyslexia. If by changing font size on the computer the child's fluency improves with increasing size then a visual problem may be indicated.
As some visual dyslexics experience problems even with the large print in first grade books it may be impossible to both increase the size and have enough words to read for a fair test for all.
It is a better test for those visual dyslexics that only started to have their problems about third grade when print size in their school books gets smaller. It might also be helpful to stop near a billboard with very large print and ask if the print looks the same as that in their books.
A careful observer can often listen to a child's speech and determine if any language or auditory processing problems are likely to lead to reading problems and need to be addressed. In an ideal world discussions about vision and how a child see the written word would also be included. As visual dyslexia is unlikely to produce any noticeable problems before school age it is important to at least have a discussion about their vision if reading problems occur.
Visual intervention should be tried when there is an indication that visual problems with seeing the printed page are present. As See Right Dyslexia Glasses have a money back guarantee they are a low financial risk and are very effective in removing visual dyslexia associated visual problems.