One of the best things you can do when you consider implementations that claim to make a better experience for disabled people is to first understand the disability.
What will come as a surprise to many (including vendors that market products claiming their font/use of a font making reading better for people with dyslexia) is that dyslexia is a processing disability and is not tied to visual reading cues.
Yup, you read that right.
Fonts do NOT affect readability for people with dyslexia.
How do you know that Sam, you might ask.
Why the National Center for Biotechnology Information, a branch of National Institutes of Health have produced a research study.
The effect of a specialized dyslexia font, OpenDyslexic, on reading rate and accuracy:
Results from this alternating treatment experiment show no improvement in reading rate or accuracy for individual students with dyslexia, as well as the group as a whole. While some students commented that the font was "new" or "different", none of the participants reported preferring to read material presented in that font. These results indicate there may be no benefit for translating print materials to this font.
Recently, two specialized typefaces or fonts "OpenDyslexic" (OD; Gonzalez, 2012) and "Dyslexie" (Boer, 2008) have been developed that purport to increase readability for those with dyslexia. These fonts differ from the other, more traditional fonts because the letters have been designed to have thicker or "heavier" lines near the bottom of the letters (See Fig. 1). The typeface developers of these fonts claim that this "heaviness" prevents the letters from turning upside down for readers with dyslexia, and makes it easier for people with dyslexia to distinguish individual letters while reducing reading errors and the effort it takes to read text (http://www.studiostudio.nl/en/information/).
Perhaps, the typeface developers developed this font based on the same misconception that dyslexia is characterized by letter reversals, what is commonly held by teachers (Washburn et al., 2013). However, four decades of research on dyslexia suggests reading difficulties stem from more basic deficits in alphabetic and phonological coding are the probable causes of the disorder rather than visual, semantic, or syntactic deficits (Vellutino, Fletcher, Snowling, & Scanlon, 2004).
The development of the OD font may have been developed as the result of a common misunderstanding of dyslexia. Many new teachers believe dyslexia is caused by a deficit in visual perception (Allington, 1982; Bell, McPhillips, & Doveston, 2009; Hudson, High, & Al Otaiba, 2007; Wadlington & Wadlington, 2005; Washburn, Joshi, & Binks, 2011a, Washburn, Joshi, & Binks-Cantrell, 2011b; Washburn et al., 2013), which may have originated in a very early use of the term "word blindness" (Das & Das, 2009) and perpetuated by the fact that many students with dyslexia have letter reversals. While some with dyslexia do report difficulty with vision, there is little evidence to support that this is related to dyslexia (Christenson, Griffin, & Taylor, 2001; Fletcher, Foorman, Shaywitz, & Shaywitz, 1999). In fact, emerging readers commonly reverse letters as they consolidate and make sense of the sound-symbol system (Adams, 1998).
Given the press and popular support of using a specialized font as a remedy for dyslexia, it is critical to highlight that results from this study failed to identify any positive effect for using it. Currently, there is no documentation to support a specialized font is an evidence-based practice. Teachers, administrators, and parents need to be aware of the lack of empirical data supporting any positive effects of OD on reading before altering all written material into a dyslexia-friendly font.
Inert interventions may in fact cause other forms of harm, in depriving resources (time and financial) away from those interventions that have demonstrated efficacy. While the intervention studied here, a freely available font, does not have costs associated with purchasing it, there are financial and time cost associated with downloading it and transferring print materials to the new font. That time and resource could be use on other interventions that are more likely to improve students' reading ability. Further, the use of unsubstantiated interventions can impact the credibility of the profession, and lead to the public losing trust in special educators (Lilienfeld, Lynn, & Lohr, 2015).
Finally, the most harm may come when students who have already experienced significant struggle and academic failures related to learning to read, have yet another experience with failure when they are not able to read significantly better in a font designed to do so. A repeated failure experience can further damage students' self-efficacy and academic self-esteem.
And, our friends in the UK, they have a guide and guess, what, none of it is about fonts! Dyslexia friendly style guide - British Dyslexia Association
Yes scientific findings can and often do contradict the financial ventures of marketing spin.
NO - implementing a "font" is not effective or beneficial to people with dyslexia, instead causes harm, AND takes away time and resources that could have been put towards developing more usable and accessible content and delivery.
The more you know, the better decisions you can deliver to your audiences.
Have a great weekend ya'll!
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Samantha Evans, CAE, ICE-CCP, MBA (she/her)
The Accessible CAE
sam.evans@accessibilityassociation.org
Certification Director
Intl. Assoc. of Accessibility Professionals, a division of G3ict
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