Unadjusted proportion (95% CIs) of students agreeing or strongly agreeing that smoking causes different diseases promoted in GHWs or tobacco control advertising from 2006 onwards by survey year and smoking status among students who had seen a cigarette pack within the previous 6 months (weighted data)
| χ2 Statistic and p value* | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Smoking… | Years GHW used prior to plain packaging introduction | NSNS % (95%CI) | SNS % (95%CI) | ES % (95%CI) | CS % (95%CI) | Total % (95%CI) | Year | Smoking status | Interaction of year and smoking status |
| 2011 (weighted N) | (2150) | (349) | (830) | (405) | (3733) | ||||
| 2013 (weighted N) | (2558) | (253) | (653) | (286) | (2851) | ||||
| Not a plain packaging health warning | |||||||||
| Is addictive | 2007, 2009, 2011 | ||||||||
| 2011 (%) | 88 (87 to 90) | 90 (87 to 92) | 90 (88 to 92) | 89 (87 to 92) | 89 (88 to 90) | χ2(1)=1.51, p=0.22 | χ2(3)=0.50, p=0.92 | χ2(3)=6.37, p=0.01 | |
| 2013 (%) | 87 (86 to 89) | 88 (86 to 91) | 89 (87 to 91) | 88 (85 to 92) | 88 (86 to 89) | ||||
| Is toxic (from tobacco smoke) | 2007, 2009, 2011 | ||||||||
| 2011 (%) | 81 (79 to 83) | 77 (73 to 80) | 84 (82 to 86) | 86 (83 to 89) | 82 (80 to 83) | χ2(1)=0.45, p=0.50 | χ2(3)=5.24, p=0.16 | χ2(3)=5.34, p=0.15 | |
| 2013 (%) | 80 (78 to 83) | 76 (72 to 80) | 84 (81 to 86) | 86 (82 to 89) | 81 (79 to 83) | ||||
| Clogs arteries | 2006, 2008, 2010, 2012 | ||||||||
| 2011 (%) | 81 (79 to 83) | 81 (77 to 84) | 84 (82 to 87) | 84 (80 to 87) | 82 (80 to 84) | χ2(1)=2.23, p=0.14 | χ2(3)=1.21, p=0.75 | χ2(3)=2.19, p=0.53 | |
| 2013 (%) | 79 (77 to 82) | 79 (76 to 82) | 83 (80 to 86) | 82 (78 to 86) | 80 (78 to 82) | ||||
| Post-plain packaging Set 1 warning from 1 October 2012 | |||||||||
| Causes diseases in toes and fingers (gangrene) | 2006, 2008, 2010, 2012 | ||||||||
| 2011 (%) | 88 (86 to 89) | 89 (86 to 91) | 89 (87 to 91) | 84 (80 to 88) | 88 (86 to 89) | χ2(1)=0.00, p=0.97 | χ2(3)=18.03, p<0.001 | χ2(3)=2.34, p=0.50 | |
| 2013 (%) | 88 (85 to 91) | 89 (86 to 92) | 90 (87 to 92) | 85 (80 to 89) | 88 (86 to 91) | ||||
| Causes mouth cancer | 2006, 2008, 2010, 2012 | ||||||||
| 2011 (%) | 94 (93 to 95) | 93 (91 to 96) | 95 (94 to 97) | 92 (90 to 94) | 94 (93 to 95) | χ2(1)=3.33, p=0.07 | χ2(3)=18.29, p<0.001 | χ2(3)=8.66, p=0.034 | |
| 2013 (%) | 96 (95 to 96) | 95 (93 to 97) | 96 (95 to 98) | 94 (91 to 96) | 95 (95 to 96) | ||||
| Causes blindness | 2007, 2009, 2011 | ||||||||
| 2011 (%) | 50 (47 to 52) | 45 (40 to 50) | 49 (46 to 53) | 56 (52 to 61) | 50 (47 to 52) | χ2(1)=42.44, p<0.001 | χ2(3)=8.14, p=0.043 | χ2(3)=0.85, p=0.84 | |
| 2013 (%) | 60 (58 to 63) | 55 (50 to 60) | 60 (57 to 63) | 67 (62 to 71) | 60 (58 to 63) | ||||
| Harms unborn babies | 2007, 2009, 2011 | ||||||||
| 2011 (%) | 95 (94 to 96) | 92 (89 to 94) | 94 (93 to 96) | 91 (88 to 94) | 94 (93 to 95) | χ2(1)=0.84, p=0.36 | χ2(3)=25.81, p<0.001 | χ2(3)=3.08, p=0.38 | |
| 2013 (%) | 94 (93 to 95) | 91 (88 to 93) | 94 (92 to 95) | 90 (86 to 94) | 93 (92 to 95) | ||||
| Causes lung cancer | 2007, 2009, 2011 | ||||||||
| 2011 (%) | 98 (98 to 99) | 98 (96 to 99) | 97 (96 to 98) | 94 (92 to 96) | 97 (97 to 98) | χ2(1)=1.37, p=0.24 | χ2(3)=37.45, p<0.001 | χ2(3)=0.82, p=0.84 | |
| 2013 (%) | 98 (97 to 98) | 97 (96 to 98) | 96 (95 to 97) | 93 (90 to 96) | 97 (96 to 98) | ||||
| Causes emphysema | 2006, 2008, 2010, 2012 | ||||||||
| 2011 (%) | 82 (80 to 84) | 79 (75 to 83) | 89 (87 to 91) | 89 (87 to 92) | 84 (82 to 86) | χ2(1)=0.58, p=0.45 | χ2(3)=14.78, p=0.002 | χ2(3)=7.97, p=0.047 | |
| 2013 (%) | 83 (81 to 85) | 80 (77 to 84) | 90 (88 to 92) | 90 (88 to 93) | 85 (83 to 86) | ||||
| Post-plain packaging Set 2 warning from 1 August 2013 | |||||||||
| Is a leading cause of death | 2006, 2008, 2010, 2012 | ||||||||
| 2011 (%) | 76 (74 to 78) | 70 (66 to 75) | 72 (69 to 75) | 71 (67 to 76) | 74 (72 to 76) | χ2(1)=18.82, p<0.001 | χ2(3)=10.35, p=0.016 | χ2(3)=3.55, p=0.31 | |
| 2013 (%) | 81 (79 to 83) | 76 (72 to 79) | 77 (75 to 80) | 77 (73 to 81) | 80 (78 to 81) | ||||
| Increase the risk of having a heart attack | 2006, 2008, 2010, 2012 | ||||||||
| 2011 (%) | 92 (91 to 93) | 88 (86 to 91) | 92 (90 to 93) | 88 (85 to 90) | 91 (90 to 92) | χ2(1)=1.87, p=0.17 | χ2(3)=28.34, p<0.001 | χ2(3)=1.93, p=0.59 | |
| 2013 (%) | 91 (90 to 92) | 87 (85 to 90) | 91 (89 to 93) | 87 (84 to 90) | 90 (89 to 91) | ||||
| Doubles risk of stroke | 2007, 2009, 2011 | ||||||||
| 2011 (%) | 83 (81 to 85) | 81 (77 to 84) | 83 (80 to 86) | 81 (76 to 85) | 83 (81 to 84) | χ2(1)=0.13, p=0.72 | χ2(3)=8.57, p=0.036 | χ2(3)=2.93, p=0.40 | |
| 2013 (%) | 84 (82 to 87) | 82 (78 to 85) | 84 (81 to 86) | 82 (77 to 86) | 84 (81 to 86) | ||||
Items grouped according to whether they were used as a warning with the introduction of plain packaging.
In total, 104 students had missing data on the smoking status variable and were excluded from analyses. Missing data on the different items over the two surveys ranged from 5 to 74.
*Analyses adjusted for covariates of sex, age, school education sector, state and smoking status. CS, smoking in past week/established smokers; ES, experimental smokers; GHW, graphic health warning; NSNS, non-susceptible never-smokers; PP, plain packaging; SNS, susceptible never-smokers.