Many claims are being made about the advantages of conducting surveys on the Web. However, there has been little research on the effects of format or design on the levels of unit and item response or on data quality. In a study conducted at the University of Michigan, a number of experiments were added to a survey of the student population to assess the impact of design features on resulting data quality. A sample of 1,602 students was sent an e-mail invitation to participate in a Web survey on attitudes toward affirmative action. Three experiments on design approaches were added to the survey application. One experiment varied whether respondents were reminded of their progress through the instrument. In a second experiment, one version presented several related items on one screen, while the other version presented one question per screen. In a third experiment, for one series of questions a random half of the sample clicked radio buttons to indicate their answers, while the other half entered a numeric response in a box. This article discusses the overall implementation and outcome of the survey, and it describes the results of the imbedded design experiments.
