Scope attribute should be used correctly on tables
How to Fix the Problem
  If you are using HTML5, check that the scope attribute is only
  being used on th elements. If you are using HTML 4, check that
  the scope attribute is only being used on th and
  td.
  Finally, check that the value of the scope is either row or
  col, but nothing else.
  Add scope attribute values to all th elements that
  do not have one.
  The markup necessary to convey the relationship between header cells and data
  cells in data tables that are not complex can be accomplished using the
  scope attribute. The scope attribute tells the
  browser and screen reader that everything under the column is related to the
  header at the top, and everything to the right of the row header is related to
  that header.
Applying the scope attribute to a table in markup looks like this:
Good Example
<table>
<caption><strong>Greensprings Running Club Personal Bests</strong></caption>
  <tr>
    <th scope="col">Name</th>
    <th scope="col">1 mile</th>
    <th scope="col">5 km</th>
    <th scope="col">10 km</th>
  </tr>
    
  <tr>
    <th scope="row">Mary</th>
    <td>8:32</td>
    <td>28:04</td>
    <td>1:01:16</td>
  </tr>
    
  <tr>
    <th scope="row">Betsy</th>
    <td>7:43</td>
    <td>26:47</td>
    <td>55:38</td>
  </tr>
    
  <tr>
    <th scope="row">Matt</th>
    <td>7:55</td>
    <td>27:29</td>
    <td>57:04</td>
  </tr>
    
  <tr>
    <th scope="row">Todd</th>
    <td>7:01</td>
    <td>24:21</td>
    <td>50:35</td>
  </tr>
</table>
  Note that the top headers for Name, 1 mile, 5 km and 10 km are all marked up
  with th elements, as are the row headers for Mary, Betsy, Matt
  and Todd. Each of these header cells have also been given the
  scope attribute values of col or
  row depending on whether they are column or row header cells.
Why it Matters
  The scope attribute makes table navigation much easier for screen
  reader users, provided that it is used correctly. Incorrectly used,
  scope can make table navigation much harder and less efficient.
A screen reader operates under the assumption that a table has a header and that this header specifies a scope. Because of the way screen readers function, having an accurate header makes viewing a table far more accessible and more efficient for people who use the device.
Rule Description
  The scope attribute must be used correctly on tables in
  accordance with either HTML4 or HTML5 specifications to enable efficient table
  navigation for screen reader users.
The Algorithm (in simple terms)
Ensures that the scope attribute is used correctly on tables.
 
              

