Table 2

Characteristics of warning manipulations in studies in the meta-analysis

VariablePictorial (k=37)Text (k=37)
kPer centkPer cent
Number of different warnings viewed
 1 warning14381541
 2–64 warnings22592054
 Not reported1325
Number of times viewed each warning
 1 time32863286
 2–5 times514514
Number of exposure sessions
 1 session36973697
 2–4 sessions1313
Days from exposure to assessment
 0 days (immediate assessment)36973697
 1–28 days1313
Exposure medium
 Just warning411616
 Warning on a 2D pack21572054
 Warning on a 3D pack822822
 Not reported41138
Exposure channel
 Printed or paper411411
 Cigarette pack822822
 Not reported411411
Label order
 Not reported616514
 NA (1 label or all shown at once)16431849
Warning exposure controlled by…
 Not reported616616
Nature of pictorial warnings
 Image only38
 Image with text3389
 Not reported13
Pictorial text vs comparison text
 Matched completely1643
 Did not match1643
 NA (pictorial condition had no text)38
 Not reported26
  • All but a single study69 assessed individuals only directly after exposure.

  • 2D, 2-dimensional; 3D, 3-dimensional; k, number of effect sizes; NA, not applicable.