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The title says it all - Reading through Colour
The public could reasonably assume, from
this title, that coloured filters can facilitate reading in at least some people with dyslexia. |
A further problem is that whatever conclusion you are trying to draw from the data, nearly all of the studies are at high risk of bias in multiple domains due to major flaws in study design and data interpretation. For that reason, it is hard to draw meaningful conclusions from these studies, whatever it is that the authors think they are trying to treat.
For example, a systematic review that Bruce Evans has criticised (wrongly)for 'asking the wrong question' was published in the house journal of the College of Optometrists in September 2016. However, a selection criterion for this review was treating subjects with visual stress (according to the multitude of diagnostic criteria that exist) and some measure of reading as an outcome measure. That review found that almost all studies were at high risk of bias in multiple domains and those that were not, offered no support for the use of coloured overlays and lenses. The review asked the right question - what is the risk of bias of the included studies?- It is the conclusions that have not been appreciated by visual stress enthusiasts.
If it is not reading or dyslexia that is being treated, it is reasonable to ask why is the dependent variable of most of the trials some measure of reading? - either naturalistic text or the Wilkins' Rate of Reading Test and why are participants so often reading impaired?
A pseudo-systematic review of controlled trials on visual stress using Intuitive Overlays or the Intuitive Colorimeter by Bruce Evans and Peter Allen published in 2016 in the Journal of Optometry (reviewed in my blog of Jan 2018) contained the following statement.....
'Individually prescribed coloured filters have been shown to improve reading performance in people with visual stress but are unlikely to improve the phonological and memory deficits associated with dyslexia and are therefore not a treatment for dyslexia'
This statement makes no sense. Dyslexia is poor reading that is why it is called- dys-lexia. It is wrong to think of garden-variety poor readers and poor readers with dyslexia and the prevalence of dyslexia depends on exactly where you draw the line along the spectrum of reading ability. So it is being claimed that coloured filters are a treatment for dyslexia, albeit in the subgroup who have the putative disorder visual stress.
The argument is that 'visual stress' is an impediment to reading and by removing that impediment reading should improve. When enthusiasts state that coloured filters are not a treatment for reading impairment one might, with equal logic, state that improving phonological awareness is not a treatment for dyslexia but a treatment for poor phonological awareness.
Elsewhere, in a letter to the British Medical Journal, Bruce Evans and Peter Allen state that
'we know of more than twenty studies of the effects of overlays on reading rate, and few of them were included in these reviews. These studies published in peer reviewed journals include various controls for placebo effects none of which provides for an improvement in reading rate as great as that observed with overlays'
Ignoring that fact that all the studies showing an improvement in reading rate are at high risk of bias. Evans and Allen clearly state that overlays can improve reading rate albeit in people with VS or the overlap group with VS and dyslexia. For that reason, they are saying it is a treatment for that sub-population of poor readers.
The argument is that 'visual stress' is an impediment to reading and by removing that impediment reading should improve. When enthusiasts state that coloured filters are not a treatment for reading impairment one might, with equal logic, state that improving phonological awareness is not a treatment for dyslexia but a treatment for poor phonological awareness.
Elsewhere, in a letter to the British Medical Journal, Bruce Evans and Peter Allen state that
'we know of more than twenty studies of the effects of overlays on reading rate, and few of them were included in these reviews. These studies published in peer reviewed journals include various controls for placebo effects none of which provides for an improvement in reading rate as great as that observed with overlays'
Ignoring that fact that all the studies showing an improvement in reading rate are at high risk of bias. Evans and Allen clearly state that overlays can improve reading rate albeit in people with VS or the overlap group with VS and dyslexia. For that reason, they are saying it is a treatment for that sub-population of poor readers.
The title of Arnold Wilkins' book is Reading Through Colour - therefore, you might reasonably think that if you have a reading disorder such as dyslexia your reading might improve as a result of using Intuitive Overlays and Precision Tinted Lenses if you belong to the subgroup with visual stress.
In my experience that is what the majority of parents who buy into this system (and other tinting systems) for their children are expecting both in the short and long term. Unfortunately, the best available evidence says otherwise.
In my experience that is what the majority of parents who buy into this system (and other tinting systems) for their children are expecting both in the short and long term. Unfortunately, the best available evidence says otherwise.
