Abstract
<roman><b>Background:</b></roman> Many countries mandate transparency and consent when personal data are handled by online services. However, most users do not read privacy policies or cannot understand them. An important challenge for technical communicators is empowering users to manage their online privacy responsibly. <roman><b>Literature review:</b></roman> Research suggests that privacy visualizations may alleviate this problem, but existing approaches are incomplete and under-researched. <roman><b>Research questions:</b></roman> 1. How can we design a privacy rating that optimally empowers users with different levels of knowledge about and awareness of online privacy? 2. How do users react to such a privacy rating, in terms of usability, perceived usefulness, and trust in online services? <roman><b>Methodology:</b></roman> We developed Privacy Rating, a tool for mapping and visualizing the privacy of online services. The tool was subjected to user research (N = 30) focusing on usability, perceived usefulness, and effects on trust. To establish the effects on trust, participants were exposed to a website with either a positive or a negative privacy rating. <roman><b>Results:</b></roman> The Privacy Rating appeared to be usable and useful for lay users, and it had a significant effect on users’ trust in the online service. Users indicated that they would like the visualization to become an established standard, preferably approved by an independent organization. <roman><b>Conclusions:</b></roman> The Privacy Rating is a user-friendly privacy visualization covering all relevant aspects of privacy. We aim to bring the tool to the market and make it a standard, ideally supported by an independent trustworthy organization.