Re: HTML Table Markup

Andrew concludes:
In reality, we are concerned with what works with existing assistive technologies, so we might not implement one of the examples above because it
may not work (or because we'd need to spend the time to test it out).
Sailesh:
In all of Andrew's examples, there is a row of column headers. I understant Bruce's viewpoint: is a header row needed for  every simple data table, even a small one like a 3 by 3? In reality, such a table can be navigated as a layout table and absence of headers does not really  make a huge difference. But if the table had more columns and rows then a row of headers is necessary. Like a sighted user, a screen reader user might want to run down a column of values, and then navigate left-right to read related values. Without column headers, the screen reader would read  the contents of the first row as headers.
Screen readers are designed typically to read the first row as column headers and first column of data as row headers by default and  they work even if no th is used. i.e. even if first row and first column have td without scope or id-headers.
So it is up to the author. If there is content which  the author intends the user to read as a data table, then use a header row and appropriate markup. A th stands out and might help other than non-visual users too.
Sailesh Panchang
Senior Accessibility Engineer 
Deque Systems,11180  Sunrise Valley Drive, 
4th Floor, Reston VA 20191
Tel: 703-225-0380 Extension 105 
E-mail: sailesh.panchang@deque.com
Fax: 703-225-0387
    * Look up <http://www.deque.com> *