Ensuring accessibility in DITA tables is crucial for making content inclusive and usable for individuals with disabilities. Accessibility involves providing content in a way that can be consumed by a diverse audience, including those who may rely on assistive technologies.

Some of the best ways to ensure that DITA tables are accessible are to use semantic markup, clear header information, include a table summary, manage data cell content, provide alternative text, and provide table captions.

Semantic Markup

To enhance accessibility, use semantic markup that provides meaning and structure to the table content. DITA itself promotes semantic structuring of content. For instance, use appropriate elements like <table>, <tgroup>, <thead>, <tbody>, <row>, <entry>, and <colspec>. Semantic elements convey the purpose and relationships between parts of the table.

Header Information

Use header elements to identify table headers, both for columns and rows. In DITA tables, <sthead> is used for column headers and <stentry> for row headers. This ensures that screen readers and other assistive technologies can convey the relationships between headers and data.

Table Summary

Include a brief and meaningful summary of the table’s purpose using the <title> element. This helps all users, including those using screen readers, understand the context and relevance of the table.

Data Cells

Ensure that data cells contain information that is clear, concise, and contextually meaningful. Avoid using complex or nested tables that can confuse assistive technologies. Ensure the content makes sense when linearized (read from left to right and top to bottom).

Alternative Text

If the table contains images, use meaningful alternative text for those images. This is essential for individuals who rely on screen readers. Include <image> elements with appropriate alt attributes.

Table Captions

If the table requires a caption, use the <title> element to provide a clear and concise title for the table content. This helps screen reader users understand the purpose of the table.

Example

    <table>
      <title>Population by Country</title>
      <tgroup cols="3">
        <colspec colname="col1" colnum="1" colwidth="1*"/>
        <colspec colname="col2" colnum="2" colwidth="1*"/>
        <colspec colname="col3" colnum="3" colwidth="1*"/>
        <thead>
          <row>
            <stentry>Country</stentry>
            <stentry>Population (Millions)</stentry>
            <stentry>Capital</stentry>
          </row>
        </thead>
        <tbody>
          <row>
            <entry>USA</entry>
            <entry>331</entry>
            <entry>Washington, D.C.</entry>
          </row>
          <row>
            <entry>Canada</entry>
            <entry>38</entry>
            <entry>Ottawa</entry>
          </row>
          <!-- More rows... -->
        </tbody>
      </tgroup>
    </table>
  

In this example, the <title> element provides a summary of the table’s content. The <thead> section defines column headers using <stentry>, and the main content is organized in the <tbody>. Each <entry> element contains meaningful data, ensuring that the table is both structurally and semantically accessible. When converted to HTML or other output formats, this semantic structure will help assistive technologies convey the table’s content effectively.