Table header cells must describe data cells

Checks header/data associations to ensure each header cell contributes meaning to one or more data cells.

• Extra or orphaned headers create confusion in table navigation
• Users hear irrelevant headers that do not describe data
• Complex table interpretation becomes unreliable

Use valid scope, headers, or table structure so each header maps to data cells.

Bad Example:

<table>
  <tr><th>Unused Header</th></tr>
  <tr><td>Value</td></tr>
</table>

Good Example:

<table>
  <tr><th scope="col">Product</th><th scope="col">Price</th></tr>
  <tr><td>Headphones</td><td>$99</td></tr>
</table>

• Using <th> for visual style only
• Missing scope in simple tables
• Broken associations in complex matrix tables

• Use screen reader table navigation to confirm header announcements
• Check header-to-cell mapping in accessibility inspector
• Validate table semantics in automated tooling