I have no idea how accessible it is, but you could also take a look at the Survey Monkey website.  They have a free version and a pro version.  I've received a lot of surveys over the years that have been created using Survey Monkey.  I would be curious to know whether the tool is accessible as far as doing the creation of a survey.  The surveys themselves are a series of webpages that use things like radio buttons, dropdown lists, text boxes, etc., for actual data entry by the survey taker. 

Brian
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