Tables are critical for conveying certain types of information. They make it much easier to make sense of data, and to draw conclusions from large amounts of information. They are used in every technology discussed in this document.
Therefore, it is critical to ensure that tables are produced in such a way that they can be read and manipulated with screen access software. The following tips should help to guide you in building tables that everyone can use.
Avoid creating pseudo tables, which are only visually presented as tables, and not semantically created as tables in the software package you are using. For instance, some people will use tab stops to create “tables” in Word, but these cannot be understood as tables by screen access users as they are really just text so far as the software is concerned. These pseudo tables are also far less flexible for designers, and more difficult to update and change than if the creator of the document used a real table.
Use as much structural markup as is available in your chosen design tool.
In HTML or PDF, a creator can specify header rows and columns as well as a brief summary of the purpose of any given table. These elements all should be used to assist users reading the table.
In Word, on the other hand, row headers are not available, but column headers should be used, as well as a brief textual description of the purpose of a table to clarify its purpose.
It’s important to avoid having empty header cells. Since header cells provide context for users, of screen access software, empty cells will create confusion when reviewing a data table.
Layout tables, tables intended to create a visual appearance, and not to provide information in a tabular form, are especially difficult to make useful to all users. They make it harder to resize information, can confuse reading order for screen access users, and can make it much harder for mobile device users to find information on a page or document that will make sense. Avoid them wherever possible.
Tables with merged cells and other complex layouts are more likely to confuse users, both sighted and blind. Even if a cell contains “duplicate” information it is easier to read if the table is laid out as a proper grid.