Methods
RCT in 83 smokers over 3 weeks. After a seven-day baseline phase (smoking from usual tobacco packaging), participants were randomized to one of two adhesive labels groups for the remaining 14 days: Standard health warning labels (HWLs) featuring enhanced efficacy messages (experimental group) or unmodified standard HWLs (control group). Participants attached these labels to their tobacco packaging and recorded their cognitions and smoking behavior once daily using Smartphones. Multilevel structural equation modeling was used to test theorized effects of the labels on self-efficacy, risk perception, and intentions to quit.