Table 3

Impact of chemical messages and pictorial warnings

Effect size for chemical messages (d)Effect size for pictorial warnings (d)12
Negative affectMedium (0.31)Large (0.54)
Thinking about the harms of smokingSmall (0.15)Small (0.18)
Thinking about the messageSmall (0.01)Large (0.61)
Perceived likelihood of harm from smokingSmall (0.04)Small (0.00)
Number of conversations about label in the past weekSmall (0.15)Medium (0.26)
Quit intentionsSmall (0.04)Small (0.18)
  • Cohen’s d of <0.20 is a small effect,  0.20–0.50 is a medium effect and >0.50 is a large effect.64