When it comes to creating accessible content, the usual focus is on headings, images and use of colour. These are all important issues that can really help deal with accessibility, but they are not everything.
The other important areas relate to the use of tables, font styling and text justification. Text justification is the spacing of text across a page or column. Full justification, where both the left and right margins are aligned, is favoured by designers because it creates a clean and block look. However, this form of text formatting can create major issues for some people.
Who is affected by text formatting?
The first group is people who use screen magnification (usually people with low vision). As they scroll back and forth across the document having a fixed block left margin and a ragged right margin (left-justified text) makes it easier for them to find the next line of text. A fully justified text layout makes the task of finding the edges of text more difficult and therefore more time consuming.
For other people, the main issue with fully justified text is that of ‘kerning’. This is the variable spaces inserted between letters and words to create the perfectly lined up margins on both sides. For people with specific eye conditions or cognitive or learning difficulties the effect of kerning is that it creates uneven white spaces which make lines of print hard to follow.
Fully justifying text can also present problems for people with dyslexia, where the large uneven spaces between words and sometimes letters within words can create what’s been termed “rivers of white” that run down the page and also make the line of print hard to follow. Readers find it more difficult to find the end of sentences and can repeatedly lose their place.
Top tips for dealing with text justification issues
- Use left justification as a default and wherever possible as this addresses both margin and kerning issues.
- If you must use full justification, ensure that normal word spacing is preserved. Desktop publishing programs InDesign and QuarkXPress have more sophisticated text justification tools that balance accessibility and achieve the required look. Microsoft Word allows for justification of words but not letters, so it’s more likely this will cause readability problems.
- Be careful with hyphenation. It can help with justification issues, particularly in narrow columns, but use it modestly and consider readability when breaking up words over lines.
- Fonts can also help or hinder accessibility. As a rule of thumb, web safe fonts work for accessibility too. Remember that some people will use the text enlargement function to levels of 200%, so the font must work at these magnifications.