Experiments on Multiple Requests for Consent to Data Linkage in Surveys

It is increasingly common for researchers to link survey data to administrative data. If several administrative data sources are of interest, respondents are required to give consent to each of them, meaning that multiple consent questions have to be included in one survey. Existing literature suggests that individual consent varies widely between data sources and over time, but little is known about how respondents process multiple consent requests in a single survey. Using an online access panel in Great Britain, we conducted a set of experiments in two surveys to explore multiple consent requests (covering five domains or data sources). In the first study we experimentally varied the format of the request, testing three versions: 1) a sequence of pages (with one response per domain), 2) all five requests on the same page (with one response per domain), and 3) a single request (with one joint request covering all five domains). We also varied the order of the domains. We find that average consent rates do not differ by format, but asking a less sensitive or easier-to-comply request first yields slightly higher average consent rates than asking a more sensitive request first. We repeated the order experiment in a second study, using an independent sample from the same panel, and adding two more order conditions. We find average consent rates are not affected much by order, but the consent to individual domains is affected by order. However, we fail to replicate the pattern of consents found in the first study. We conclude that the order in which multiple consent requests is asked does matter, but in complicated ways that depend on the particular outcomes in which one is interested. Objective knowledge and subjective comprehension of the consent process, and confidence in the decision are largely unaffected by format or order.