For several years we have been investigating how various ways of communicating disclosure risk and harm to respondents affects their willingness to participate in surveys. These experiments, which used vignettes administered to an online panel as well as a mail survey sent to a national probability sample, have demonstrated that (a) the probability of disclosure alone has no apparent effect on people’s willingness to participate in the survey described, (b) the sensitivity of the survey topic has such an effect, and (c) making explicit the possible harms that might result from disclosure also reduces willingness to participate, in both the vignette and the mail experiments. As a last study in this series we experimented with different ways of talking about disclosure risk in informed consent statements that might more plausibly be used in real surveys, again using vignettes. The study used a 4 (topic) x 6 (confidentiality assurance) design. Two of the topics were sensitive (sex, money) and two were not (work, leisure time). The confidentiality statement assured confidentiality “except as required by law” or “to the fullest extent of the law” or gave an estimated probability of disclosure (one in a million). Three of the statements contained, in addition, the following reassurance: “In our experience at the Survey Research Center, no one, to the best of our knowledge, has ever been harmed through a breach of confidentiality.” Mode (face-to-face), sponsor (National Institutes of Health), length (15 minutes) and incentive ($5) were kept constant across the 24 vignettes. The survey was administered to 7200 members of an online panel by Market Strategies Inc. The presentation analyzes the main and interactive effects of topic sensitivity, type of assurance, and
reassurance on the basis of experience on subjects’ willingness to participate in the survey described.