  Digital tools play an important role in fighting the current global COVID-19
pandemic. We conducted a representative online study in Germany on a sample of
599 participants to evaluate the user perception of vaccination certificates.
We investigated five different variants of vaccination certificates, based on
deployed and planned designs in a between-group design, including paper-based
and app-based variants. Our main results show that the willingness to use and
adopt vaccination certificates is generally high. Overall, paper-based
vaccination certificates were favored over app-based solutions. The willingness
to use digital apps decreased significantly by a higher disposition to privacy,
and increased by higher worries about the pandemic and acceptance of the
coronavirus vaccination. Vaccination certificates resemble an interesting use
case for studying privacy perceptions for health related data. We hope that our
work will be able to educate the currently ongoing design of vaccination
certificates, will give us deeper insights into privacy of health-related data
and apps, and prepare us for future potential applications of vaccination
certificates and health apps in general.
