Behavior	Behavior change	Injunctive norm	Descriptive norm	Attitudes	Intentions	Perceived behavioral control
Number of items and response categories	Never; approx. 25% of times; approx. 50% of times; always	Much less often; less often; no change; more often; much more often	Three items (Friends, Family, People important for me): Totally disagree; disagree; Neither/nor; agree; totally agree	Two items (Friends, Where I live): Totally disagree; disagree; Neither/nor; agree; totally agree	Four items (Necessary, Very dangerous, Fun, Stupid): Totally disagree; disagree; Neither/nor; agree; totally agree	Two items (Will avoid, Likely that I will): Totally disagree; disagree; Neither/nor; agree; totally agree	One item Very hard to avoid; hard to avoid; Neither/nor; Easy to avoid; Very easy to avoid
N	375	375	1129 2-on-1: 515 Mobile: 294 RUI: 320	1129 2-on-1: 515 Mobile: 294 RUI: 320	1129 2-on-1: 515 Mobile: 294 RUI: 320	1129 2-on-1: 515 Mobile: 294 RUI: 320	1129 2-on-1: 515 Mobile: 294 RUI: 320