2 Core Concepts of Digital Accessibility

Overview

This guide outlines key elements for making course materials accessible. We’ll explore core concepts, the content types they affect, and considerations for applying them. We’ll cover: Readable Text, Headings, Descriptive Links, Tables, Color Choice, Alternative Text, and Captions and Transcripts.

Readable Text

Readable text primarily affects PDF documents and scanned items. It has two key criteria: visual readability without strain, and technological accessibility by tools like screen readers. Many scanned items are flat images with no readable text, making them inaccessible to screen readers and potentially visually straining (e.g., poor quality, askew text).

You can confirm readable text by attempting to highlight it with your cursor. If highlightable, the text is accessible.

For scanned items, scan quality is paramount. High-quality scans enable Optical Character Recognition (OCR) software to create readable text. Whenever possible, prioritize digitally published content from journals or publishers, as these are inherently more accessible than scans.

How to make text searchable in a PDF: Tools like Adobe Acrobat Pro have built-in OCR capabilities. Within our learning management system, Anthology Ally in Canvas can also identify and remediate accessibility issues in uploaded documents.

Headings

Headings apply to Word documents, PowerPoint presentations, PDFs, Canvas content, and web pages.

Headings are structural elements that organize your document into logical sections, not just stylized text. Properly formatted headings provide essential navigation for screen reader users, allowing them to jump quickly between sections. For sighted users, they offer visual cues for scanning and finding information. In Word, headings can also automatically generate a table of contents.

How to use headings: Always use your software’s built-in heading features. In Word and Canvas, use specific heading styles (Heading 1, Heading 2, etc.). In PowerPoint, utilize built-in title boxes for structural purposes. Correct heading structures in Word typically transfer well when converted to PDF.

Descriptive Links

Descriptive links apply to any digital content with hyperlinks: Word documents, PowerPoint presentations, Canvas content, and web pages.

A descriptive link is hyperlink text that clearly explains the link’s destination and content. For example, instead of pasting a long URL or saying “Click here,” use descriptive text like “Top US Headlines for March 20, 2024” or “Visit The Institute for Teaching and Learning.”

Descriptive links inform users exactly where they’re going and what to expect. This is vital for all users, especially those using screen readers, who would otherwise hear every character of a URL spoken aloud. Descriptive names also help differentiate multiple links on a page.

How to implement descriptive links:

• Word and PowerPoint: Highlight the text, right-click, and select ‘Hyperlink’.
• Canvas: Highlight the text, click the link icon in the toolbar, then choose external or course link.

Tables

Tables are used in Word documents, PowerPoint presentations, PDFs, Canvas, and web pages – wherever tabular data is presented.

Crucially, tables should only be used for presenting data, not for controlling document layout or visual formatting. Assistive technologies are designed to interpret tabular data structures. Using tables for layout will confuse screen readers, leading to a nonsensical experience.

A ‘tabular data’ table has logical columns and rows for organizing information. A ‘format table’ is used for visual arrangement without structured data.

Merged cells are generally inaccessible. AT relies on standard column and row structures to navigate tables. Merged cells disrupt this, making content difficult for screen reader users to understand.

For complex tables or multiple datasets:

• Break them into several smaller, simpler tables.
• Consider alternative ways to convey data, like charts, graphs, or bulleted lists.
• Consult campus resources like the Assistive Technology Resource Center or The Institute for Learning and Teaching for guidance.

Color Choice

Color choice is relevant to all digital content types.

Color contrast is the difference in lightness between text and its background. Sufficient contrast is vital for people with color blindness, low vision, and light sensitivity.

Key elements of contrast include the perceived brightness difference (expressed as a contrast ratio) and font size. Larger text can be legible with lower contrast, but smaller text requires higher contrast.

How to ensure high contrast: Use a color contrast checker. Free tools like WebAIM online contrast checker or Colour Contrast Analyser (TPGi) allow you to input colors to verify they meet Web Content Accessibility Guidelines (WCAG) standards for sufficient contrast (aim for AA level for most text).

Alternative Text

Alternative text (alt text) applies to any digital content with images, such as Word documents, PowerPoint presentations, Canvas, and web pages.

Alt text is a short, textual description embedded in an image. Its primary purpose is to convey an image’s visual information to users who cannot see it, especially those using screen readers.

How to add alt text:

• Word and PowerPoint: Right-click an image, select ‘View Alt Text,’ and enter your description in the pane.
• Canvas: In the page editor, click the image, then ‘Image Options,’ and enter text in the alt text pane.

When writing alt text, focus on the image’s key takeaway, information, or meaning. Context is crucial; the same image may need different alt text depending on its use. Keep descriptions concise, ideally under 120 characters. For example, for the painting below, Claude Monet’s “Impressions, Sunrise,” the alt text could depend on the focus of the class: is it about painting techniques, historical context, or something else?

For complex images (graphs, diagrams, etc., requiring detailed explanation): Provide a separate, longer description in a companion document with a link/reference. Alternatively, describe the image in the main document’s body text and refer to that description in the alt text (e.g., “Claude Monet’s ‘Impressions, Sunrise,’ full description in the body text below the image”).

Captions and Transcripts

Captions and transcripts are essential for making audio and video content accessible, wherever it is used.

Captions are for video content, providing time-synchronized text of the audio track. Transcripts are for audio-only content, offering a written version of what’s said. While providing transcripts with video is good practice (allowing users to read or search), captions and transcripts are not interchangeable. Videos must have captions to be accessible, and audio-only content (like podcasts) must have a transcript.

There are two main caption types:

• Open captions are “burned” into the video and cannot be turned off.
• Closed captions are more common; they can be toggled on/off and customized.

Many platforms offer automatic captioning, but auto-generated captions are rarely perfect. Always review and edit them for accuracy, especially with subject-specific jargon.

When creating your own audio/video: Record with good audio quality to improve automatic captioning accuracy.

When using external content:

• Videos (e.g., YouTube): Check if captions are already available. Use platform filters to find captioned videos.
• Podcasts/Broadcasts: Look for accompanying transcripts on the website before selecting content.

Next Steps

In this module, we’ve covered core accessibility concepts. Now that you understand how they affect your course materials, it’s time to apply them to common file types like Microsoft Word and PowerPoint. While we’ve covered essential concepts, many other areas of accessibility can affect your course materials.