  With the increasing awareness and concerns around privacy, many service
providers offer their users various privacy controls. Through these controls,
users gain greater authority over the collection, utilisation, and
dissemination of their personal information by the services. However, these
controls may be buried deep within menus or settings, making them difficult for
a user to access. Additionally, the terminology used to describe privacy
controls can sometimes be confusing or technical, further complicating the
user's ability to understand and use them effectively. This is especially true
for health websites, as users often share sensitive information about their
health and well-being. While many privacy controls have been proposed to
protect user data on these sites, existing research focuses on individual
controls (e.g., privacy policies or cookie opt-outs) rather than providing a
comprehensive overview of the privacy landscape. In addition, many studies
concentrate on the technical aspects of privacy controls without considering
the usability of these features from a user's perspective. This paper aims to
fill the gaps in the existing work by analysing four privacy controls, namely
privacy nudge, privacy notice, privacy policy, and privacy setting, and
evaluating their usability on the top 100 most visited health websites. First,
we define usability attributes for each privacy control in three website visit
scenarios; the guest, registering, and log-in visits. These attributes include
awareness, efficiency, comprehension, functionality, and choice. Then, we
design a survey template based on these attributes and scenarios and collect
data about privacy controls. Next, we analyse the availability and usability of
each privacy control on health websites. Finally, we provide suggestions for
improving the design of these privacy controls based on the data analysis
results.
