Study design, setting, and participants
We studied whether PP and new harsher health warnings increased negative affect, avoidant responses, and quitting intentions. We used a survey experiment in which we randomly assigned respondents to one of the five experimental conditions (used as control or treatment groups). The experimental conditions were designed by the researchers by combining the old or currently used package design elements, with the intention of disentangling the individual differential effects of the design elements on negative affect, avoidant responses, and quitting intentions.An online survey experiment was conducted among university students in Ankara, the capital city of Turkey, in June-July 2021. In the 2020–2021 academic year, there were 21 universities and 229,251 university students (110,413 male and 118,838 female) in Ankara, the target population [