Wave 1

Possession of smartphone, mobile phone, PC, tablet and/or e-book reader; social media use: account with user name and password at selected providers (Google, Facebook, Twitter, LinkedIn, Xing); trust in institutions (Google, Facebook, Bundesamt für Statistik, Universitätsforscher) with regard to the protection of personal data and reasons for this assessment; probability scale with regard to the protection of personal data at the above-mentioned institutions and reasons for this assessment; agreement with the import of personal data of the social insurance institutions to the survey data; general personal trust; awareness of the EU General Data Protection regulations (GDPR) ; knowledge test: goals of the GDPR (open); feeling of invaded privacy by the following institutions: Google, Facebook, government agencies, university researchers; general privacy concerns.

Wave 2

Possession of smartphone, mobile phone, PC, tablet and/or e-book reader; social media use: account with user name and password with selected providers (Google, Facebook, Twitter, LinkedIn, Xing); trust in institutions (Google, Facebook, Federal Statistical Office, university researchers) with regard to the protection of personal data; general personal trust; awareness of the EU General Data Protection regulations (GDPR); knowledge test: goals of the GDPR (open); consent to the storage of various personal data by Facebook or Google (name, e-mail address, home address, date of birth, telephone number, income, marital status, number of children, current location, Internet browser history, account names from other social media and data received from third parties); feeling of invasion of privacy by the following institutions: Google, Facebook, government agencies, university researchers; general privacy concerns.

Wave 3

Possession of smartphone, mobile phone, PC, tablet and/or e-book reader; social media use: account with user name and password at selected providers (Google, Facebook, Twitter, LinkedIn, Xing); trust in institutions (Google, Facebook, Federal Statistical Office, university researchers) with regard to the protection of personal data; general personal trust; awareness of the EU General Data Protection regulations (GDPR); knowledge test: goals of the GDPR (open); concerns about privacy in general; comprehensibility of excerpts of the contents of the EU General Data Protection regulations (GDPR) (resp. on passenger rights in the event of denied boarding and flight delays); estimated popularity of smartphones (proportion of smartphone owners per 100 adult Germans); repetition of the question on trust data collecting organisations (Google, Facebook) with regard to the protection of personal data and general personal trust; readiness for data exchange by Google (or Facebook or the Federal Statistical Office) for research purposes (or for commercial purposes).

Demography: sex; age (year of birth); federal state; school education; professional qualification.

Additionally coded was: running number; respondent ID; experimental groups GDPR Info; duration (reaction time in seconds); used device type to complete the questionnaire.