How do I add a summary or title attribute for simpletable or choicetable elements?

Our documentation requires HTML table tags to include summaries or title attributes for accessibility requirements, but I haven't been able to find an existing attribute that I use for this purpose. We are only using simpletable and choicetable. How have you addressed accessibility needs for tables in your documentation? Focus Areas: BPEL | DITA | ebXML | IDtrust | OpenDocument | SAML | UBL | UDDI
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