Visual tracking. DS was dx with dyslexia and we took him to see a Behavioural Optometrist to get his visual tracking assessed. He was skipping words across the lines. She gave him glasses and blue/aqua overlays. This has helped a lot. www.babo.co.uk/
At my primary we try things like coloured rulers with a gap for the words with a lot of the DC who struggle with reading. It really helps some, has no affect on others. We just give it a try and it's nothing particularly scientific in our case. But if it's working for your DC have you investigated Irlen syndrome? Some BOs as Sallybear recommends, do deal with coloured glasses etc to help Irlen syndrome.
Ds2 had overlay and now glasses, he has fantastic progress. He is colour blind and the red helps make the contrasts better for him. His Opt. Said he doesn't have irlens but glare is very different for some colour blind children. She also said he probably would just stop using them naturally when he was reading better.