Research Research Association between tobacco plain packaging and Quitline calls: a population- based, interrupted time-series analysis Jane M Young nternationally, Australia is a leader MPH, PhD, FAFPHM, Abstract Professor in Cancer in tobacco control policies that Epidemiology1 Objectives: To investigate whether the introduction of tobacco plain packaging Ireduce community exposure to in Australia from 1 October 2012 was associated with a change in the number of Ingrid Stacey BSc(Hons), tobacco-related harm. In December calls to the smoking cessation helpline, Quitline, and to compare this with the Biostatistical Officer2 2012, Australia became the first coun- impact of the introduction of graphic health warnings from 1 March 2006. Timothy A Dobbins try in the world to enact legislation Design and setting: Whole-of-population interrupted time-series analysis in BMath, PhD, New South Wales and the Australian Capital Territory between 1 March 2005 Senior Lecturer1 mandating plain packaging for all tobacco products.1 The Tobacco Plain and October 2006 for the comparator, graphic health warnings, and October Sally Dunlop 2011 and April 2013 for the intervention of interest, tobacco plain packaging. PhD, Packaging Act 2011 (Cwlth) is designed Research Associate2 to prevent tobacco industry promotion Main outcome measure: Weekly number of calls to the Quitline, after adjusting Anita L Dessaix for seasonal trends, anti-tobacco advertising, cigarette costliness and the MPH, by simultaneously reducing pack number of smokers in the community. Manager, attractiveness and increasing the size Cancer Prevention2 Results: There was a 78% increase in the number of calls to the Quitline of graphic health warnings. The legis- David C Currow associated with the introduction of plain packaging (baseline, 363/week; peak, BMed, MPH, FRACP, lation required manufacturers to pro- 651/week [95% CI, 523–780/week; P < 0.001]). This peak occurred 4 weeks 2 Chief Executive duce plain packs with new warnings after the initial appearance of plain packaging and has been prolonged. The from 1 October 2012. From 1 Decem- 2006 introduction of graphic health warnings had the same relative increase in 1 Cancer Epidemiology and ber 2012, plain packaging became calls (84%; baseline, 910/week; peak, 1673/week [95% CI, 1383–1963/week; Services Research (CESR), P < 0.001]) but the impact of plain packaging has continued for longer. Sydney School of Public compulsory for all tobacco products. Health, University The new plain packs are olive green Conclusions: There has been a sustained increase in calls to the Quitline after of Sydney, the introduction of tobacco plain packaging. This increase is not attributable to Sydney, NSW. and devoid of brand design. Tele- anti-tobacco advertising activity, cigarette price increases nor other identifiable 2 Cancer Institute NSW, phone numbers for the national causes. This is an important incremental step in comprehensive tobacco Sydney, NSW. smoking cessation helpline, Quitline, control. jane.young@ feature prominently on the packs. sydney.edu.au Plain packaging legislation exists to introduction of the Tobacco Plain date the start of the intervention. Sim- encourage smokers to quit and dis- Packaging Act, complementing a ilarly, 1 March 2006 was the date of MJA 2014; 200: 29–32 courage the uptake of smoking.1 Quit- recent report of smokers’ feedback.7 the introduction of graphic health doi: 10.5694/mja13.11070 line is a free resource that can be used We did this by investigating the warnings on cigarette packaging. We by smokers who are motivated and impact of the introduction of tobacco looked at Quitline call numbers seeking support to quit. Therefore, the plain packaging on Quitline calls. To before and after these dates for the volume of calls to cessation helplines provide context, we compared the two interventions. Call data from 1 has frequently been used as one indi- impact on Quitline calls of the intro- April 2004 to 28 February 2006 were cator of changes in interest in quitting duction of tobacco plain packaging provided by Macquarie Telecom (Syd- in response to population-wide cessa- with the nationwide introduction of ney, Australia) and from 1 March 2006 tion policies and programs.2-6 graphic health warnings on cigarette to 31 March 2013 by the Telstra Ana- The best level of evidence for evalu- packaging in 2006.8 The null hypothe- lyser (Telstra, Melbourne, Australia). ating a whole-of-population initiative sis was that there would be no change This study did not require institu- such as tobacco plain packaging is an in call numbers, adjusting for known tional ethics approval as it did not interrupted time-series analysis. In confounders. involve data about individuals. The exactly the same way in which obser- study received no external funding. vational studies have been used to Reporting of the study complies with The Medical Journaldefine of the Australia association ISSN: 0025-between lung Methods the STROBE (STrengthening the 729X 20 Januarycancer 2014 200and 1 29-32tobacco (because ran- Reporting of OBservational studies in ©The Medical Journal of Australia 2014 domised studies are unethical in such We used an interrupted time-series Epidemiology) consensus guidelines www.mja.com.au analysis to investigate trends in the a context), before-and-after evalua- for reporting observational studies.9 Research tion, controlling for secular trends, is weekly volume of calls from New the optimal design for assessing the South Wales and the Australian Cap- effects of population-wide initiatives. ital Territory to the Quitline. Potential confounders In this study, we sought to examine As plain packs were phased in from An increase in anti-smoking advertis- Online first 13/01/14 behavioural change resulting from the 1 October 2012, we considered this ing in mass media such as television is MJA 200 (1) · 20 January 2014 29 Research 1 Autoregressive integrated moving average (ARIMA) modelling results for the plain packaging and graphic health warning interventions Peak call volume attributable to Number of calls in intervention (calls/week) Time Exponential decay week intervention to Duration rate of call volume Intervention was introduced Estimate (95% CI) Relative increase peak of effect following peak Plain packaging 363 651 (523–780) 78% 4 weeks 43 weeks 14% per week Graphic health warnings 910 1673 (1383–1963) 84% 12 weeks 20 weeks 60% per week 2 Weekly calls to Quitline, target audience rating points (TARPs) and cigarette Another potential confounder is price relative to income, before and after the introduction of plain tobacco cigarette costliness. We followed packaging and graphic health warnings Wakefield et al10 and calculated ciga- Plain tobacco packaging rette costliness as the ratio of the average quarterly recommended retail Calls to Quitline price for a pack of the two top-selling TARPs 2.0 800 Cigarette price Australian cigarette brands (obtained from the retail trade magazine Aus- tralian Retail Tobacconist, volumes 65 600 1.5 to 87) to the average weekly earnings Plain packaging in the same quarter obtained from the Australian Bureau of Statistics.11 1.0 400 Finally, the number of smokers in the community can be a potential confounder. We obtained data on 200 0.5 smoking prevalence during the study periods from Health Statistics New Cigarette price relative to income (%) Total weekly calls to Quitline/TARPs 12 0 0 South Wales, and this was applied to Oct Apr Oct Apr quarterly figures for population size 2011 2012 2012 2013 from the Australian Bureau of Statistics13 to calculate the number of smokers in the community. Data for Graphic health warnings the first quarter of 2012 were not available, so we used results carried 2.0 forward from the final quarter of 2011. 3000 Statistical analyses 1.5 As the data for weekly number of calls 2000 to the Quitline were autocorrelated (each value was correlated with the 1.0 previous value) we used autoregres- Graphic health warnings sive integrated moving average 1000 (ARIMA) analysis in SAS version 9.3 0.5 (SAS Institute Inc). ARIMA models enable the investigation of changes Cigarette price relative to income (%) Total weekly calls to Quitline/TARPs 0 0 over time while accounting for sea- Apr Oct Apr Oct sonal variation and background 2005 2005 2006 2006 trends in such things as the effects of television anti-tobacco advertising, changes in cigarette pricing relative to a potential confounder as it increases tute NSW). TARPs are a product of weekly earnings and number of the number of calls to the Quitline.2,3,6 the percentage of the target audience smokers in the community. In ARIMA We ascertained weekly target audi- exposed to an advertisement (reach) modelling, comprising model investi- ence rating points (TARPs) for adver- and the average number of times a gation, estimation and diagnostic tisements broadcast in NSW and the target audience member would be checking, we followed the methods of ACT during the periods of interest, exposed (frequency), adjusted for the Box et al (Appendix; online at using OzTAM (Australian television length of the advertisement. For mja.com.au).14 audience measurements) for adults example, 200 TARPs might represent A single model fitted to the entire aged 18 years and older for free-to-air 100% of the target audience receiving 7-year period of Quitline call data did and cable television using established the message twice on average over a not meet technical criteria for model methods (unpublished report pre- specified period,