What makes print more readable for the visually impaired?

November 30, 2016
NTNU has run the largest readability study of printed text for the visually impaired to date. Credit: Thinkstock

The number of visually impaired people in Norway is high. The Norwegian Association of the Blind and Partially Sighted estimates that 180,000 Norwegians have been diagnosed with an eye condition. Even more people have poor eyesight due to natural visual deterioration. Researchers at the Norwegian University of Science and Technology's (NTNU)  Research Laboratory for Universal Design (the UU lab) have published the biggest readability study of printed text for the visually impaired evLr done in Norway.

The results provide clear criteria on what print characteristics are essential to enable the to also read printed text.

Everyone has the right to participate in society

Norwegian law is abundantly clear: individuals with disabilities should have the opportunity to participate in society on an equal basis with others. This includes access to the written word. Universal design is a necessary prerequisite for this to happen.

"We've tested 4.6 per cent of everyone in Norway with visual disorders, and found that and contrast affect the most for society at large," says Jonny Nersveen, who heads up the UU Lab at NTNU in Gjøvik.

"The criteria are relevant for everything from public letters to school textbooks, literature, advertising and newspapers," he says.

The test group consisted of 830 individuals with an eye disease. In the study, researchers tested how well the visually impaired participants were able to read text in the typefaces Helvetica, Times New Roman, Verdana, Frutiger, Tiresias, Tiresias bold, Scala bold, Scala sense and Scala sans bold.

What makes print more readable for the visually impaired?
Study results show that type size matters the most for readability, but the font choice is less important. Credit: Marte Foss / NTNU

Legibility was tested in different sizes, using both normal and bold type. Researchers also checked for font legibility with and without serifs (i.e. the small lines attached to letters in some fonts). In addition, the readers graded the readability of text with different contrast levels between the font and the background.

Font size most important

The results show that typeface size matters the most for readability, whereas the font choice is less important.

"Somewhat surprisingly, we found that it's not necessary to increase the size of the font that much to make readability good enough. This is a positive discovery, since economic and space-saving considerations often make it preferable to use a smaller font," says Nersveen.

"We found that setting the font at 12 point was a well-defined point for readability, which adequately addresses the needs of . If the typeface is smaller than 12 point, readability drops dramatically. Normal contrast allows more than 80 per cent of the visually impaired to read text in 12-point font. It's a very positive finding," he says.

Font size varies from font to font. For the sake of comparison, font sizes are therefore scaled to correspond to the Times New Roman font, which this study used as its font size basis.

What makes print more readable for the visually impaired?
Contrast was shown to matter for readability. Although black letters on a white background worked best for the majority of participants, it turns out we’re not as contrast sensitive as we might have guessed. Credit: Marte Foss / NTNU

Contrast proved to make some difference in readability. Although black letters on a white background worked the very best for most study participants, we are apparently not as contrast sensitive as we might have anticipated. Serifs, which were originally meant to increase readability, sometimes proved to have the opposite effect, but the differences were small. Bold type, on the other hand, increased readability as long as the font size was not too small.

Hoping for spillover effect

Assistant Professor Eivind Arnstein Johansen, now at NTNU's Norwegian Media Technology Lab, has worked as a designer and typographer and sees a need for this type of study in the industry. He believes the results will primarily be applied by the public sector in guiding the design of printed text, but hopes that the study will also provide an increased understanding for newspapers and other printed media.

"The print industry has had a lot of opinions and assumptions about what works best in terms of typeface, font sizes and contrast," Johansen says, so "it's good to now know for sure what will work for most people. If this study results in more publishers increasing the font size, it will be a positive step for both visually impaired and normal-sighted individuals."

Explore further: In brief: Larger font packs more emotional punch

Related Stories

In brief: Larger font packs more emotional punch

May 9, 2012
Bigger words – literally those printed in larger font size – elicit stronger emotional brain responses, reports a study published May 9 in the open access journal PLoS ONE.

New free font available to help those with dyslexia

October 1, 2012
(Medical Xpress)—A new font tailored for people afflicted with dyslexia is now available for use on mobile devices, thanks to a design by Abelardo Gonzalez, a mobile app designer from New Hampshire. Gonzalez, in collaboration ...

Most prescription labels fail to meet guidelines, risking dosage errors

July 9, 2014
Small print and poor printing on prescription labels handed out by pharmacists may be misread and may lead to errors in taking medication, according to new research by the University of Waterloo and CNIB (Canadian National ...

Study suggests 'hard to read' fonts may increase reading retention

June 1, 2011
(Medical Xpress) -- Researchers from Indiana University and Princeton, in a paper published in Cognition, describe two experiments they conducted that appear to show reading retention improves when fonts that are considered ...

Recommended for you

Three million Americans carry loaded handguns daily, study finds

October 19, 2017
An estimated 3 million adult American handgun owners carry a firearm loaded and on their person on a daily basis, and 9 million do so on a monthly basis, new research indicates. The vast majority cited protection as their ...

More teens than ever aren't getting enough sleep

October 19, 2017
If you're a young person who can't seem to get enough sleep, you're not alone: A new study led by San Diego State University Professor of Psychology Jean Twenge finds that adolescents today are sleeping fewer hours per night ...

Across Asia, liver cancer is linked to herbal remedies: study

October 18, 2017
Researchers have uncovered widespread evidence of a link between traditional Chinese herbal remedies and liver cancer across Asia, a study said Wednesday.

Eating better throughout adult years improves physical fitness in old age, suggests study

October 18, 2017
People who have a healthier diet throughout their adult lives are more likely to be stronger and fitter in older age than those who don't, according to a new study led by the University of Southampton.

Global calcium consumption appears low, especially in Asia

October 18, 2017
Daily calcium intake among adults appears to vary quite widely around the world in distinct regional patterns, according to a new systematic review of research data ahead of World Osteoporosis Day on Friday, Oct. 20.

New study: Nearly half of US medical care comes from emergency rooms

October 17, 2017
Nearly half of all US medical care is delivered by emergency departments, according to a new study by researchers at the University of Maryland School of Medicine (UMSOM). And in recent years, the percentage of care delivered ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Nov 30, 2016
Why didn't they test APH's famous APHont ?? That's *designed* for high legibility.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.