Data collection poses specific challenges, including accessibility, trust, and user motivation. The following sections discuss how these issues affected our design.
Advocates of web accessibility—designing so that pages and sites are still useful for people with special needs and disabilities—often say that designing a site that is accessible will also create a site that is more usable for everyone. This was not just a theoretical consideration in our case, since, with a target audience whose members were approaching or past retirement, age-related vision impairment was a real concern. Some 72% of Americans report vision impairment by the time they are 45 years of age.
The other side of the age issue—one rarely spoken of, for fears of appearing discriminatory—is that older people use computers and the Internet in fewer numbers and with less ease than younger people who grew up with computers in their lives. (Individuals with higher incomes generally use computers and the Internet more, however, so those age-related effects were mitigated in our sample group.) Respondents who are stymied by a confusingly designed survey are less likely to give accurate information—or, indeed, to complete the survey at all. In our case, as in all such projects, it pays to recall that essential adage: know your audience.
While accessibility is a functional issue—a respondent cannot complete a survey if she can't ...