Coloured Filters and Autism Ranking: Insufficient/Mixed evidence

Current Research

Current Research Studies

We have identified eight scientific studies of the use of Irlen lenses for people with reading difficulties published in peer-reviewed journals. However, because it is unclear if these studies included people on the autism spectrum, we have not included them in our evaluation.

We have identified five scientific studies of coloured overlays for people with autism published in peer-reviewed journals.

We have identified one scientific study which looked at coloured glasses and at coloured overlays.

The studies with autistic participants included a total of more than 140 individuals aged from 7 to 26 years old.

  • Some of the studies (Ludlow et al, 2006; Ludlow et al, 2008; Whitaker et al - epub) reported an increase in reading speed in some participants
  • Some of the studies (Ludlow et al, 2012; Whitaker et al – epub) reported an improvement in emotion recognition in some participants
  • One of the studies (Ludlow et al, 2008) reported an improved ability to distinguish between different objects
  • The only study which looked at glasses and overlays (Ludlow and Wilkins, 2009) reported a wide range of improvements including better motor coordination skills, better social skills and greater confidence.

Status of Current Research Studies

There are a number of limitations to all of the research studies published to date. For example

  • One study (Ludlow, 2009) had a single participant.
  • None of the controlled studies were randomised and none were blinded.
  • All of the studies were undertaken by the same group of researchers, none of whom were independent of the intervention being studied. Those researchers may therefore have been biased towards the intervention, however unconsciously.

For a comprehensive list of potential flaws in research studies, please see "Why some autism research studies are flawed."

06 Nov 2017
Last Review
01 Apr 2016
Next Review
01 Apr 2019