Dunlop SM, Dobbins T, Young JM, et al. Impact of Australia's introduction of tobacco plain packs on adult smokers' pack-related perceptions and responses: results from a continuous tracking survey. BMJ Open 2014;4:e005836.
An error in coding resulted in 428 ineligible cases being included in this study. These ineligible cases were part of a concurrent pilot study of recruitment via mobile phone. The coding error was applied to the descriptive statistics and regression analyses, but not the time-series analyses. The correction of this error does not change the results or conclusions of the study, but for clarification, the following corrections are noted:
1. The sample size in the ‘Participants’ section of the Abstract should be 15 375.
2. In the Method section, ‘Analyses for this study are limited to smokers interviewed between April 2006 and May 2013 (total n=15 745)’ should read ‘Analyses for this study are limited to smokers interviewed between April 2006 and May 2013 (total n=15 375)’.
3. In the Results section, ‘the increase in cognitive and emotional responses occurred after 3 months (cognitive: from 13% in September 2012 to 20% in January 2013; emotional: from 13% to 27%)’ should read ‘the increase in cognitive and emotional responses occurred after 3 months (cognitive: from 13% in September 2012 to 21% in January 2013; emotional: from 13% to 29%)’.
4. In the Results section, ‘Compared with the preplain packaging period (August/September 2012), scores on the scale were significantly higher in immediate postplain packaging period (December/January) and in the 5–6 month postplain packaging period (April/May). These effects were independent of any differences between the samples on sociodemographic or smoking characteristics, antismoking advertising activity, or increases in cigarette costliness’ should read ‘Compared with the preplain packaging period (August/September 2012), scores on the scale were significantly higher in immediate postplain packaging period (December/January). This effect was independent of any differences between the samples on sociodemographic or smoking characteristics, antismoking advertising activity, or increases in cigarette costliness’.
5. In the Results section, ‘says something good about them (from 27% to 76%), influences the brand they buy (from 27% to 77%), makes their brand stand out (from 22% to 78%), is fashionable (from 27% to 80%)’ should read ‘says something good about them (from 27% to 78%), influences the brand they buy (from 27% to 79%), makes their brand stand out (from 22% to 81%), is fashionable (from 27% to 82%)’.
Corrected versions of tables 1 and 3, figures 1–3, supplementary figures 1 and 2 are below. The corrected versions of the figures result in minor changes to estimates for some data points, with no change in overall patterns of the data.
Table 1.
Sample characteristics from the Cancer Institute's Tobacco Tracking Survey (CITTS) April 2006 to May 2013 (smokers only; n=15 375)
| N | Per cent | |
|---|---|---|
| Sex | ||
| Female | 8126 | 50 |
| Male | 7249 | 50 |
| Age (years) | ||
| 18–29 | 2265 | 21 |
| 30–55 | 8260 | 48 |
| 55+ | 4848 | 31 |
| Socioeconomic status | ||
| Low | 6443 | 41 |
| Moderate | 3951 | 27 |
| High | 4808 | 33 |
| Smoking frequency | ||
| Daily | 13659 | 88 |
| Weekly | 917 | 6 |
| Less than weekly | 799 | 6 |
| Smoking | ||
| Low | 5871 | 41 |
| Moderate | 5705 | 38 |
| High | 3384 | 22 |
| Quit attempts in past 12 months | ||
| None | 9189 | 60 |
| At least one | 5975 | 40 |
| Year | ||
| 2006 | 1600 | 10 |
| 2007 | 2289 | 15 |
| 2008 | 2094 | 13 |
| 2009 | 2135 | 14 |
| 2010 | 2146 | 14 |
| 2011 | 2157 | 14 |
| 2012 | 2126 | 13 |
| 2013 | 828 | 5 |
Ns are unweighted, per cents are weighted for age, sex and regional residence.
Table 3.
Results from linear regression models predicting Graphic Health Warning Impact and Negative Pack Perceptions from month of interview in the plain packaging and comparison periods
| Comparison period (2011–2012) |
Plain packaging period (2012–2013) |
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M | (SD) | β | 95% CI | p Value |
M | (SD) | β | 95% CI | p Value |
|||
| GHW impact | ||||||||||||
| Month | ||||||||||||
| August/September | NA | 2.67 | (0.93) | Ref | ||||||||
| October/November | 2.57 | (0.90) | Ref | 2.75 | (0.97) | 0.01 | −0.15 | 0.21 | 0.747 | |||
| December/January | 2.62 | (0.99) | −0.01 | −0.25 | 0.21 | 0.847 | 2.86 | (1.18) | 0.09 | 0.05 | 0.50 | 0.017 |
| February/March | 2.77 | (0.89) | 0.10 | −0.19 | 0.58 | 0.323 | 2.75 | (1.17) | 0.06 | −0.11 | 0.41 | 0.262 |
| April/May | 2.67 | (0.96) | −0.01 | −0.52 | 0.48 | 0.930 | 2.79 | (1.22) | 0.03 | −0.12 | 0.29 | 0.403 |
| Negative pack perceptions | ||||||||||||
| Month | ||||||||||||
| August/September | NA | 3.95 | (0.76) | Ref | ||||||||
| October/November | 4.03 | (0.60) | Ref | 3.96 | (0.75) | 0.03 | −0.45 | 1.10 | 0.412 | |||
| December/January | 4.11 | (0.64) | 0.06 | −0.43 | 1.46 | 0.286 | 4.47 | (0.65) | 0.25 | 2.52 | 4.06 | <0.001 |
| February/March | 4.08 | (0.59) | 0.03 | −1.40 | 1.88 | 0.775 | 4.56 | (0.63) | 0.31 | 2.58 | 4.38 | <0.001 |
| April/May | 4.03 | (0.69) | 0.07 | −1.61 | 2.80 | 0.598 | 4.67 | (0.58) | 0.34 | 3.82 | 5.20 | <0.001 |
Models controlled for demographics (sex, age, SES), smoking characteristics (frequency and level of smoking, 12 m quitting history), antismoking advertising activity (TARPs) and recent increases in cigarette costliness (% increase in past 12 weeks); M's and SD's are unweighted.
β, Standardised coefficient; GHW, Graphic Health Warnings; M, mean (range 1–5); NA, not applicable; SES, socioeconomic status; TARP, Target Audience Rating Points.
Figure 1.
Monthly proportions of smokers strongly agreeing that: (A) the graphic warnings encourage me to stop smoking (cognitive response); (B) with the graphic warnings, each time I get a cigarette out I worry that I should not be smoking (emotional response); (C) they make me feel that I should hide or cover my packet from the view of others (avoidant response) and (D) the only thing I notice on my cigarette pack is the graphic warnings (warning salience).
Figure 2.
Monthly proportions of smokers strongly disagreeing that their cigarette pack is: (A) attractive; (B) says something good about me to other smokers; (C) influences the brand I buy; (D) makes my brand stand out from other brands; (E) is fashionable and (F) matches my style.
Figure 3.
Monthly mean score for Graphic Health Warning Impact and Negative Pack Perceptions.