Results from this study suggest that the HP2010 goal of 12% smoking prevalence can be reached before 2020 if a comprehensive set of policies related to tobacco tax/price increases, smokefree air laws, mass media/educational campaigns, and cessation treatment (including improved web-based treatments and policies to improve the effectiveness of evidence-based treatments) are implemented. With all of these policies in effect simultaneously, the model projects that the HP2010 goal of 12% can be reached by 2013.
A tax increase of $0.62 and smokefree laws implemented in 2009 should help to reach the HP 2010 goal. The tax increase also should reduce smoking rates by 2% in 2010, increasing to 5% by 2020. This study also suggests that stronger policies to promote cessation treatments, in particular, can have strong effects. Evidence-based cessation treatment policies, such as improved financial access, greater healthcare provider involvement and improved quitlines, are estimated to have effects similar to those of a $2.00 tax increase. The findings also indicate that improved web-based programs and individually tailored/stepped care approaches merit further attention.
Because some policies (e.g., taxes or clean air laws) are more likely to affect quit attempts while others more directly affect treatment use (e.g., treatment coverage), their combined effect is shown to be synergistic. The effect of increased treatment use is (multiplicatively) enhanced through improved treatment effectiveness, leading to higher levels of treatment success for those making a quit attempt. Similarly, the multiplicative relationship between more quit attempts and improved treatment effectiveness implies synergies. While a growing number of studies document the synergies that occur when multiple different tobacco control policies are applied60–62
, the model synthesizes this evidence and estimates actual effects.
The results in this paper are subject to seven general limitations. First, the effect sizes for policy parameters are preliminary, due to relatively sparse data on the effects of policies on quit attempts, treatment use, and treatment effectiveness. For taxes, clean air laws, and media campaigns, in particular, research is needed to gauge the variance in how each of the policies affects quit attempts, treatment use and especially treatment effectiveness.
Second, in combining policies, it was assumed that the effect of each additional policy on quit attempts, treatment use, and treatment effectiveness depends on the percentage of the relevant population that has not already been affected by other simultaneously implemented policies. If the percentage effects were additive, the effect of policies—especially on quit attempts—would increase quite dramatically, and would further increase if the percentage increases were multiplicative. If, however, the effects of different policies cancel each other out, the effects estimated above for combined policies may be overstated.
Third, when the model was calibrated, the quit rates in the initial model were underpredicted for those aged 18–34 years and for those aged >65 years, which merits further exploration. More generally, the current levels of treatment effectiveness are subject to uncertainty. Levy et al51
suggested bounds of 50% above and 50% below estimates for treatment effectiveness. A fourth limitation relates to the use of a 10% annual decay rate for the eroding effect of policies over time in the model. Although this rate yields policy parameter estimates that are roughly consistent with studies of the effect of policies on smoking prevalence12
, the results from the model were found to be sensitive to the decay rate. Fifth, the model did not consider how the policies themselves might have a differential impact by age and gender. Sixth, the study considered the effectiveness, but did not consider the costs of implementing the policies. Finally, this paper did not consider youth initiation-oriented policies (e.g., school education, limiting youth access to cigarette purchases) or other policies (health warnings, advertising bans) that may also help to reach HP2010 objectives.
This study highlights the importance of tracking each of the components of smoking prevalence—quit attempts, treatment use, and treatment effectiveness—to understand the impact of policy changes and to identify the optimal combination of policy changes. Simulation models are a critical tool to evaluate scenarios for which there is no clear evidence regarding the impact of the policies (e.g., if different cessation treatment policies were successfully integrated and tailored to the needs of individual smokers with follow-up).
In sum, the SimSmoke
policy simulation model was used to examine the effects of multiple public health tobacco control and cessation treatment policies on the national adult quit rate. Results demonstrate that while it is not reasonable to expect that the HP2010 will be reached by 2010, if a suite of policies are implemented nationwide, the HP2010 goals are achievable within the next 5–12 years. Tax policies, smokefree laws, mass media/educational policies, and both evidence-based and promising cessation treatment policies must be implemented nationally and in all states. Policy implementation is especially critical in states with historically poor performance in tobacco control and high smoking rates.63
Because the effects of policy changes take time to unfold, policies must be implemented soon if we are to come close to reaching HP2010 targets.