Impact on users
The following is an overview of common accessibility errors in page title, text content, headings and link text and the impact on users with a disability.
Page titles
- Page titles should not be missing or empty.
- When the page title is missing or empty the screen reader user does not know what page or site they are on.
- Page titles should be legible, accurate, unique, concise and descriptive.
- If the page title is incorrect the screen reader user cannot distinguish or confirm that they have arrived at the page they require.
- Page titles should include a consistent reference to the site.
- The site name in the page serves as an added confirmation to the screen reader user of the current site and reassurance that an unexpected change in context has not occurred.
Text content
- Page content is correctly spelt and meaningful.
- All content on a site should be correctly spelt and meaningful to minimise confusion to screen reader users and also those with cognitive issues.
- Any instructions are device independent and do not depend on location or visual appearance.
- Device dependent instructions imply that functionality is restricted to particular device such as a mouse. Instructions that rely on visual cues alone, such as location or appearance, cannot be interpreted correctly by a user with a visual impairment.
- The default language is English, foreign language has been marked up correctly and the page DOCTYPE is correct.
- Screen readers rely on the correct markup of the default language and any foreign language for correct pronunciation.
- Images of text are not used in preference to HTML.
- Using images of text restricts the end user – people with low vision may have trouble reading the image text. The use of HTML allows people who require a particular visual presentation of text to be able to make adjustments as needed.
- Dates are in an unabbreviated format.
- Screen readers correctly read the date when unabbreviated. If shortened this is often more difficult for the screen reader user to understand.
Headings
- Headings should not be empty, missing or incorrect.
- Headings are used by screen reader users as a key element to guide their use of the page – empty, missing or incorrect headings can be misleading.
- Headings should be coded with H1, H2 etc. should be at the right level and nested correctly.
- Headings are used by screen reader users to navigate a page and get an idea of relative importance of the content.
- Headings should be descriptive and concise.
- Headings are used by screen reader and magnifier users to scan the page and get an overview idea of the content contained. Descriptive and concise headings enable both visually impaired and other users to do this.
Link text
- Link text should be clear, descriptive, not capitalised and avoid the use of ASCII characters.
- Screen readers read out each letter of any capitalised word as an abbreviation and are not able to interpret ASCII characters.
- Link text should be device independent.
- Restricted to a particular device such as a mouse.