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Impact of Tobacco Control on Adult per Capita Cigarette Consumption in the United States Kenneth E. Warner, PhD, Donald W. Sexton, MHA, MBA, Brenda W. Gillespie, PhD, David T. Levy, PhD, and Frank J. Chaloupka, PhD
January 11, 2014, will mark the 50th anniversary of the release of the first surgeon general’s report on smoking and health,1 widely considered to demarcate the beginning of the tobacco control era in the United States. Tobacco control has consisted of development and dissemination of information on the hazards of smoking, policy implementation, and other interventions in the public, voluntary, and private sectors. These diverse efforts are linked by their dedication to reducing cigarette smoking and, with it, the most grievous toll of disease and death ever wrought by a single product (we use the terms tobacco control, tobacco control era, and tobacco control movement throughout as shorthand to refer to the totality of these efforts). Three measures of cigarette consumption have dominated discussions of the behavioral effects of tobacco control: adult cigarette smoking prevalence, average daily cigarette consumption per smoker, and annual adult per capita cigarette consumption, the latter defined as the total number of cigarettes consumed per year divided by the population older than 17 years. Adult smoking prevalence declined 55% from 1965 to 2011, from 42.4% to 19.0%. The number of cigarettes consumed per smoker per day has been falling steadily, from a peak of nearly 34 cigarettes in 1980 to 18 in 2011.2 Adult per capita consumption, which depends on both prevalence and quantity smoked per smoker, fell 72% between 1963 (the year before the first surgeon general’s report) and 2011, from 4345 cigarettes to 1236. As impressive as these results may be, they do not fully reflect the impact of tobacco control. The assumption implicit in these comparisons is that smoking had peaked immediately before 1964 and, hence, that the contribution of tobacco control has been simply to decrease smoking from those mid-1960s levels. In point of fact, cigarette consumption was rising sharply and quite steadily from
Objectives. We assessed the impact of tobacco control on adult per capita cigarette consumption in the United States from 1964 to 2011. Methods. We used logit regression to model the diffusion of smoking from 1900 to 2011. We also projected hypothetical cigarette consumption after 1963 in the absence of tobacco control. Model predictors included historical events such as wars, specific tobacco control interventions, and other influences. Results. Per capita consumption increased rapidly through 1963, consistent with S-shaped (sigmoid) diffusion. The course reversed beginning in 1964, the year of publication of the first surgeon general’s report on smoking and health. Subsequent tobacco control policy interventions significantly reduced consumption. Had the tobacco control movement never occurred, per capita consumption would have been nearly 5 times higher than it actually was in 2011. Conclusions. Tobacco control has been one of the most successful public health endeavors of the past half century. Still, the remaining burden of smoking in the United States augurs hundreds of thousands of deaths annually for decades to come. Reinvigorating the tobacco control movement will require novel interventions as well as stronger application of existing evidence-based policies. (Am J Public Health. 2014;104:83–89. doi:10.2105/AJPH.2013.301591)
1900 through the early 1960s. It almost certainly would have continued to rise in the absence of the report and subsequent tobacco control initiatives because smoking among women was increasing rapidly at that time, paralleling the diffusion of smoking among men 2 to 3 decades earlier. The onset of the tobacco control movement stalled and eventually reversed the then rapidly growing prevalence of smoking among women.3 Three previous analyses, to our knowledge, have assessed how much higher adult per capita consumption would have been in the absence of tobacco control, reflecting the increases in smoking that would have been anticipated had the movement never materialized.4---6 In the most recent of the 3 studies, Warner found that actual per capita consumption fell by 26% from 1963 to 1987, whereas consumption likely would have been 79% to 89% higher in 1987 had it not been for the salutary effects of tobacco control.6 With no analysis of this phenomenon for a quarter of a century, we believed that it was time to estimate how much tobacco control has
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affected cigarette consumption as the movement concludes its fifth decade. Relative to previous studies, we employed a more sophisticated conceptual model to estimate tobacco control’s effects. The resulting change in methods has no impact on the qualitative conclusions of the earlier studies and indeed only a minor quantitative impact. Had the original methodology been used in our study, however, it would have overestimated the impact of tobacco control considerably.
METHODS Our analysis derives from a model of the diffusion of smoking from 1900 to 2011, one that allowed us to assess the general diffusion pattern over time while evaluating the effects on cigarette consumption of specific events and interventions. Some of the events occurred independent of any interest in smoking but affected smoking nonetheless, including the Great Depression and the nation’s major wars. All but one of the remaining events and
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interventions were clearly intended to decrease smoking, such as publication of the surgeon general’s reports and the introduction of clean indoor air laws. The remaining variable, price, is a well-established determinant of the level of smoking but is neither entirely a tobacco control variable nor a completely independent one, as we discuss later.
We regressed adult per capita consumption of cigarettes against year and the other variables. The regression model variables are presented in Table 1 and discussed in more detail in the Discussion section. The table describes the variables, provides their ranges and mean values, and presents sources and, where appropriate, comments on the variables’
construction. Parameter estimates allowed us to test whether the various events and interventions affected smoking and, if so, to what degree. To project per capita cigarette consumption from 1964 to 2011 in the absence of tobacco control, we assigned values of zero to all of the post-1963 tobacco control variables and held price constant at its 1963 value,
TABLE 1—Variables Included in the Regression Model, Along With Descriptive Information and Data Sources Variable
Year(s) Covered
Dependent variable: adult per capita cigarette consumption
1900–2011
Range or Value 54–4345
Mean
Decaya
Notes
2326
...
Sources: Alcohol and Tobacco Tax and Trade Bureau7 and US Census Bureau8; cigarette consumption is based on tax-paid cigarette sales
Year (calendar year minus 1900)
1900–2011
0–111
...
...
Captures diffusion of smoking over time
1900–2011
1.92–5.61
2.40
...
Source for 1954–2011: Orzechowski and Walker9; for 1926–
Economic indicators Cigarette price, $ (average price/pack of
1953, the tobacco producer price index and consumer price index from the Bureau of Labor Statistics10 were used to
cigarettes in 2011)
create a proxy for average price per pack; for years preceding 1926, average price per pack in 1926 was used Great Depression (unemployment rate minus 5%)
1930–1941
3.90–19.90
12.25
Yes
Source: Lebergott11
Great Depression spline (beginning in 1930)
1930–2011
1.0–83.0
...
...
Captures the modest decrease in the rate of growth of smoking following the Great Depression
Pro-smoking indicators World War I (ratio: total DoD personnel/total US adults) World War II (ratio: total DoD personnel/total US adults)
1916–1918 1941–1945
0.0028–0.045 0.005–0.12
0.013 0.087
Yes Yes
Sources: US Census Bureau8 and Carter et al.12 Sources: US Census Bureau8 and Carter et al.12
Korean War (ratio: total DoD personnel/total US adults)
1950–1953
0.014–0.034
0.016
Yes
Sources: US Census Bureau8 and Carter et al.12
Vietnam War (ratio: total DoD personnel/total US adults)
1965–1971
0.020–0.027
0.024
Yes
Sources: US Census Bureau8 and Carter et al.12
1953–1955
1.0
...
Yes
Represents major cancer and smoking scare following
Tobacco control indicators Cancer scare (dummy variable)
publication of the first definitive science linking smoking to lung cancer13 1964 surgeon general’s report (dummy variable) 1964 surgeon general spline (beginning in 1964)
1964 1964–2011
1.0 1.0–48.0
... ...
Yes ...
First surgeon general’s report1 Permanent adjustment down in the slope of the diffusion curve from its previous upward trajectory; reflects major shift in public knowledge, attitudes, and behaviors in early years of antismoking campaign
Fairness Doctrine (dummy variable)
1967–1970
0.25–1.0
...
Yes
Values: 0.25 in 1967, 0.75 in 1968 , and 1.0 in 1969–1970; period of Fairness Doctrine antismoking ads on television and radio14,15
Nonsmokers’ rights spline (beginning in 1975)
1975–2011
1.0–37.0
...
...
Reflects accelerating decrease in smoking that accompanied the nonsmokers’ rights movement and the era of clean indoor air (or smoke-free) laws beginning with Minnesota’s first model state law in 197516
1988 surgeon general’s report (dummy variable)
1988–1989
0.60–1.0
...
Yes
Values: 0.60 in 1988, 1.0 in 1989; surgeon general’s report on smoking as addictive; released in May, so first-year impact is adjusted to reflect the partial year17
Note. DoD = Department of Defense. a In year after period covered, variable takes on value of 0.75 times the preceding year’s value. Each subsequent year, the value decays by an additional 25%.
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assuming that, in the absence of tobacco control, price would have increased with the general rate of inflation. Comparing the 2011 value of this hypothetical “tobacco control--free” level of smoking with the level actually realized allowed us to estimate the impact of tobacco control on adult per capita cigarette consumption. We modeled the diffusion of smoking over time as a sigmoid or S-shaped curve, a pattern typical of the diffusion of a novel behavior or product adoption, such as cigarette smoking (novel early in the 20th century), as well as of epidemics.18 From the beginning of the 20th century to 1963, the year before the first surgeon general’s report, adult per capita cigarette consumption rose from 54 to 4345, exhibiting growth consistent with an S-shaped curve. The S-shaped curve starts slowly, rises at an exponential rate, reaches an inflection point, and then increases at a diminishing rate as it approaches an asymptotic ceiling. Although we could have performed nonlinear modeling on this S-shaped function directly, we chose to apply the inverse transformation to linearize the function, which allowed ordinary linear models to be used. For subsequent plotting of the fitted model, we transformed back to present the results on the raw scale of cigarette consumption. We used the following logit function to linearize the curve for modeling: PerCapt ð1Þ lnð Þ ¼ 0 þ Xt þ e; 6022 PerCapt where PerCapt is adult per capita consumption in year t, Xt is a vector of the independent variables in year t, is a vector of the regression parameters, and e is an error term. We used a retransformation function to obtain the predicted per capita consumption: ˇ
ˇ
d t ¼ 6022=ð1 þ exp ð0 þXt Þ Þ ð2Þ PerCap
the tobacco control era, male smoking prevalence peaked at about 55%. As noted, smoking among women was increasing at a rate virtually identical to that of men but with a 20- to 30-year lag, its rapid rise interrupted by the beginning of the tobacco control era. In the 1950s and early 1960s, men smoked an average of about 30 cigarettes per day.3 We used SAS19 and Stata20 software in conducting our statistical analyses.
RESULTS Table 2 presents the regression results. Most of the variables were highly significant. Year was included to reflect the diffusion of smoking among the population. Cigarette consumption increased significantly during World Wars I and II and the Korean War (all P < .001), whereas the estimated increase during the Vietnam War was not significant (P = .297). Smoking declined significantly during the Great Depression (P < .001). The rate of growth in smoking slowed somewhat following the depression, as reflected in the significant negative parameter estimate of the Great Depression spline (P < .001). Each of the following tobacco control--related variables decreased smoking: the
TABLE 2—Results of Multivariate Regression Analysis Predicting per Capita Consumption of Cigarettes: United States, 1900–2011 Variable Intercept
b (95% CI)
SE
t
P
–4.83 (–4.94, –4.72)
0.056
–86.28
< .001
Year
0.1326 (0.1297, 0.1355)
0.0015
91.18
< .001
Cigarette price
–0.056 (–0.108, –0.004)
0.026
–2.11
.037
9.81
< .001
World War I
11.8 (9.4, 14.2)
1.2
Great Depression
–0.0208 (–0.0254, –0.0163)
0.0023
–9.06
< .001
Great Depression spline World War II
–0.0714 (–0.0763, –0.0665) 3.21 (2.52, 3.91)
0.0025 0.35
–29.05 9.18
< .001 < .001
Korean War Cancer scare
The function to linearize the sigmoid curve required specification of an asymptote (ceiling) on adult per capita consumption, which we estimated to be 6022 cigarettes per capita. This value was derived by assuming that, in the absence of tobacco control, adult smoking prevalence eventually would have reached 55% and average daily consumption per smoker would have been 30 cigarettes. Prior to
cancer-and-smoking scare in the early 1950s (cancer scare; P < .001), publication of and extensive publicity about the 1964 surgeon general’s report (single-year effect, P = .049; long-term spline effect, P < .001), airing of the Fairness Doctrine antismoking ads on television and radio from mid-1967 through 1970 (P = .001), the adoption and spread of clean indoor air laws beginning in 1975 (nonsmokers’ rights spline, P < .001), and publication of and publicity regarding the 1988 surgeon general’s report on smoking as addiction (P = .008). Price increases also decreased cigarette consumption (P = .037). Figure 1 displays actual per capita consumption between 1900 and 2011 (dotted line), the regression fit to the latter year (solid line), and the hypothetical diffusion of adult per capita cigarette consumption in the absence of any antismoking knowledge and activity (dashed line beginning in 1964). A comparison of the lines of actual and hypothetical consumption provides a visual demonstration of the impact of tobacco control over time. In the absence of tobacco control, per capita consumption would have risen steadily, although at a decelerating rate, reaching a level of 5907 in 2011. In fact, per capita consumption plummeted. Comparing the actual value in
6.7 (3.7, 9.7) –0.234 (–0.335, –0.132)
1.5 0.051
4.49
< .001
–4.57
< .001
1964 Surgeon General’s report
–0.142 (–0.284, –0.001)
0.071
–2.00
.049
1964 Surgeon General spline
–0.0718 (–0.0815, –0.0621)
0.0049
–14.67
< .001
Vietnam War Fairness Doctrine Nonsmokers’ rights spline 1988 Surgeon General’s report
1.05
.297
–0.249 (–0.394, –0.105)
2.6 (–2.3, 7.5)
0.073
2.5
–3.43
.001
–0.0431 (–0.0554, –0.0308) –0.134 (–0.232, –0.036)
0.0062 0.05
–6.95 –2.71
< .001 .008
Note. CI = confidence interval. Values for the overall model were as follows: df = 14; F = 4215.5; P £ .001; R2 = 0.9981.
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FIGURE 1—Actual adult per capita cigarette consumption (dotted line); predicted consumption (solid line); and projected consumption in the absence of tobacco control (dashed line beginning in 1964): United States, 1900–2011.
2011 with the hypothetical value in the absence of tobacco control suggests that, had the tobacco control era never occurred, consumption in 2011 would have been 378% higher than its actual value that year.
DISCUSSION As noted, our analysis differed in methodology from that previously employed by Warner,4---6 who used linear ordinary least squares regression (untransformed) to project future per capita cigarette consumption. Linear projections indicated that, had tobacco control never occurred, per capita consumption would have reached 5075 cigarettes in 1975 and 5449 in 1978. The comparable figures from our model are 5102 and 5238, respectively, 0.5% higher than Warner’s estimate for 1975 and 4% lower for 1978. Warner’s estimate of 6154 in 1987 exceeds our estimate for that year by 11%, and it slightly exceeds the asymptotic ceiling for hypothetical consumption we selected (6022). Thus, although a linear projection was plausible for short-term projections in the earlier studies, it would not work well for more recent years, when the growth in consumption
necessarily would have slowed even in the complete absence of tobacco control, simply reflecting a conventional diffusion process. This is true even if our asymptotic ceiling may be a conservative estimate because some proportion of the population undoubtedly had reacted to the new research on smoking and lung cancer in the 1950s, prior to what we are characterizing as the tobacco control era. As well, we assumed a peak daily cigarette consumption of 30, whereas the actual historical peak was 34. Independent of the specific ceiling chosen, employing a model that represents S-shaped diffusion is both theoretically more appropriate and a better fit to the data through 1963. Regardless of the small differences, however, each of the 4 studies demonstrates that adult per capita consumption is dramatically lower than it would have been in the absence of tobacco control and that it would have been substantially higher than it was in 1963, the year prior to the beginning of the tobacco control era.
Study Limitations Our dependent variable, adult per capita consumption, measures the combined effect of smoking prevalence and daily cigarette consumption by smokers. Still, it suffers from
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a number of limitations. One is the implicit assumption that all cigarette consumption is attributable to adults, clearly not the case. Significant percentages of adolescents smoke (defined as smoking at least 1 cigarette in the past 30 days)21 and changes in their numbers, as well as the amount of cigarettes they smoke, could affect “adult” per capita consumption. Over time, smoking among adolescents has ebbed and flowed quite substantially. However, the total number of cigarettes smoked by nonadults constitutes only a small percentage of all cigarettes consumed, in part because most young smokers consume few cigarettes. And only fluctuations in that small number would matter to the relevance of adult per capita consumption as a marker of national smoking behavior. Our measure is potentially biased by the fact that changes in the age mix of the population could alter cigarette consumption, independent of any fundamental increases or decreases in smoking. So too could changes in the population’s racial/ethnic mix. For example, Hispanics’ smoking prevalence is considerably less than that of Whites, for both genders.2 Thus, the growing proportion of Hispanics in the United States could influence both smoking prevalence and consumption figures. Preliminary results from ongoing research suggest, however, that demographic shifts do not have quantitative impacts on smoking prevalence sufficient to affect our essential analysis or conclusions (J. Tam, Department of Health Management and Policy, School of Public Health, University of Michigan, oral communication, June 2013). The excellent fit of our regression was not surprising, given the inclusion of the year variable and the 3 splines (slope-shifting terms), each of which represents a major shift in the cigarette consumption trajectory. Year reflects the diffusion process through the first half of the 20th century, which would have continued thereafter in the absence of tobacco control. The Great Depression was associated with a slowing of the rate of growth in smoking that was occurring just prior to the depression. It is plausible that slowing of cigarette consumption as a result of widespread poverty over a decade or more might have a dampening effect on the growth of cigarette consumption thereafter.
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Dramatic change in the slope of the per capita consumption curve after 1964—from consistently rising to falling—is associated with the beginning of the tobacco control era (in addition to the immediate effects of the publication of the surgeon general’s report). The postreport era saw a sea change in knowledge of, attitudes toward, and behavior regarding smoking. We interpret the accelerating decrease in smoking dating from the mid-1970s as most plausibly reflecting the introduction and evolution of smoke-free indoor air laws, the principal policy marker of the nonsmokers’ rights movement.
Impact of Individual Tobacco Control Variables Individual tobacco control events and interventions clearly reduced smoking. The initial health-related shock to the escalating diffusion of smoking preceded publication of the 1964 surgeon general’s report. The first compelling scientific evidence associating smoking with lung cancer was published in 1950.13 Much of the smoking public learned about this evidence through popular publications, including a Reader’s Digest article titled “Cancer by the Carton,” published in December 1952.22 Cigarette consumption fell substantially in 1953 and 1954 and was relatively flat in 1955, a trend that we found significant in our regression. Smoking resumed its rapid upward trajectory in 1956 when the cigarette companies’ promotion of then novel filtered cigarettes falsely assured worried smokers that filtration removed the dangerous elements in cigarette smoke.23 Coverage of the iconic 1964 surgeon general’s report, among the top news stories of the year, reduced per capita consumption by about 5% from the level that would have been expected that year in its absence, a finding consistent with estimates in the literature ranging from 3% to 8%.3 Per capita consumption crept upward the next 2 years before beginning an unprecedented 4-year decline widely credited to the broadcast of free (public service announcement) antismoking messages on television and radio. The ads resulted from a Federal Communications Commission decision that cigarette smoking was a controversial public issue and hence that, under the commission’s Fairness
Doctrine, broadcasters had to donate air time to “balance” paid advertising for cigarettes. Although the antismoking messages never received comparable air time, the impact of the novel and even frightening ads was substantial. The messages ended with the banning of cigarette advertising on the airways on January 2, 1971.14,15 The most important development in tobacco control since the Fairness Doctrine likely was the emergence of the nonsmokers’ rights movement, reflected in the adoption of state clean indoor air laws.16 Initially modest in their coverage (e.g., requiring nonsmoking sections of restaurants), if still dramatic for their day, the laws have become increasingly restrictive over time. Today, approximately 30 states require that all workplaces be smoke free, including all restaurants and bars. We see the impact of the nonsmokers’ rights movement in the significant shift downward in the slope of per capita consumption marked by the nonsmokers’ rights spline in our regression. We included 1 surgeon general’s report in addition to the 1964 report in our analysis, believing that it generated the most consequential public attention since 1964: the 1988 report17 confirming that smoking involved addiction. Its parameter estimate indicated a significant downturn in smoking (P = .008). In earlier regressions, other prominent reports did not prove to be statistically significant.
Impact of Taxation Through tax increases, price can be used to decrease smoking and has been on many occasions at all levels of government.24 In the 8 years following the first surgeon general’s report, there was a surge in state excise tax increases presumed to reflect in part state legislators’ reactions to the new antismoking sentiment. This spate of tax increases substantially raised real cigarette prices (nominal prices adjusted for inflation). However, real prices declined for the next decade as states slowed their tax increases in response to concerns about interstate smuggling of cigarettes, generated by large discrepancies in state tax rates.25 Inflation-adjusted prices fluctuated thereafter, with a surge in real price in more recent years.
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Our study is consistent with a finding produced in well over 100 previous studies: price matters in cigarette consumption.24 Tax and associated price increases deserve a significant share of the credit for the recent large declines in cigarette sales, as, for that matter, do the industry’s own wholesale price increases in the face of declining sales. The cigarette price index reflects both influences. Research indicates that for every 10% increase in cigarette price, the demand for cigarettes decreases 3% to 5%. Our methods of estimating price prior to the availability of a consistent measure in 1954 required use of general data on tobacco for the period 1926 to 1953 (price index data) and the arbitrary assumption that price was constant prior to the initial availability of price index data. We tested 4 alternative means of handling the missing data for 1900 to 1925, and all yielded essentially identical results.
Influence of Wars and the Great Depression on Smoking Two factors clearly unrelated to any intention to influence smoking had significant effects: wars and the Great Depression. Indeed, World War I is often credited with playing a role in the early growth of cigarette smoking. Prior to the war, smoking cigarettes was considered effeminate. A large majority of men consumed tobacco products, but chiefly in the form of pipes, cigars, and smokeless tobacco. 26 However, cigarettes were supplied to soldiers as part of their rations during the war. Because the circumstances of warfare did not always afford the time to smoke an entire cigar or to go through the ritual of filling, lighting, and smoking a pipe, cigarettes became the GIs’ preferred method of smoking tobacco. When soldiers came home from the war addicted, cigarette smoking began its rapid escalation. Cigarettes in soldiers’ rations were valued by smoking and nonsmoking soldiers alike, serving for nonsmokers as a medium of exchange for other products and services. The increases in smoking associated with World Wars I and II and the Korean War in our study could reflect a number of factors in addition to the free availability of cigarettes to the military, however. One is simply that war-related stress
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may have induced increases in smoking not only among the soldiers but also among their families at home. We omitted the wartime variables for Desert Storm and Operation Iraqi Freedom, the first 2 wars since the end of inclusion of cigarettes in soldiers’ rations. As well, they involved fewer military personnel. When included in the regression, their parameter estimates were both nonsignificant. Smoking by soldiers in World War I was not the only contemporary factor influencing the national uptake of cigarette smoking, however. Much else was going on in the early part of the 20th century that kick started the cigarette phenomenon. This includes the 1911 breakup of the cigarette company monopoly, which fostered a vigorous competition in the sale of cigarettes; the introduction of the “American blend” of tobaccos, which made inhalation of cigarette smoke far more “palatable”; and the first modern advertising campaign, for Camel cigarettes.23,26,27 We did not include any of these factors in our model. Another factor that affected smoking in the early part of the 20th century was the Great Depression. Especially during its early years, the enormity of the economic downturn was associated with a substantial decrease in smoking. Note, however, that we evaluated consumption of manufactured cigarettes only. Thus, it is possible that some of the observed decline could reflect smokers switching to less expensive roll-your-own (RYO) cigarettes. Lacking RYO data from that period, we cannot assess how much of the downturn reflects true reductions in cigarette smoking and how much it reflects switching to RYOs. It is certainly likely that a substantial portion of the downturn represents genuine reduced consumption by smokers and perhaps some quitting.
Other Potential Variables Not Included in Our Analysis The tobacco control era is characterized by far more events and interventions than we could hope to capture in a times series analysis such as this one.23,26---28 Notably, for example, the 1998 Master Settlement Agreement (MSA) between the attorneys general of the states and the tobacco industry29 had numerous effects on the smoking environment. The MSA settled state lawsuits
against the industry for smoking-related costs in the states’ Medicaid systems, providing states with billions of dollars (although only a tiny proportion has been devoted to tobacco control). It extended the period of required release of millions of previously secret industry documents that have opened the industry’s behind-the-scenes behavior to public scrutiny. It reduced venues for cigarette advertising. Importantly—and reflected in our price index—it resulted in a significant increase in cigarette prices. We did not include the MSA per se in our regression, however, because beyond any impact through the price increase, its inclusion in earlier regressions did not show any statistically significant effect on per capita consumption. This may reflect the difficulty of properly quantifying the MSA’s contributions over time, or it could represent offsetting measures. For example, although the tobacco industry’s marketing venues were reduced by the agreement, the industry poured billions of dollars into alternative marketing opportunities. From 1998 until 2005, the industry doubled its marketing expenditures.30,31 With industry marketing the focus of so much attention in tobacco control, readers may question the absence of any measure of marketing expenditures in our analysis. We included estimates of industry expenditures in earlier versions of the regression. Although expenditures were associated with increases in per capita consumption, the association never reached statistical significance. This may have been attributable in part to the absence of good data on industry expenditures through much of the early period studied. We assumed constant expenditures (in real terms) during those years, but that obviously may have missed substantial changes in expenditure patterns that, had we had the proper data, would have demonstrated an impact of marketing on consumption. Particularly because the first decades of marketing likely played the most important role in the growth of the market, the complete absence of data during that period makes any marketing expenditure variable suspect. We also did not include marketing of a different sort—that oriented toward methods of decreasing smoking: nicotine replacement therapy (NRT) products and other smoking
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cessation pharmaceuticals, introduced in the 1980s and 1990s. We lacked adequate data on either sales or advertising expenditures. We did test the effect of a dummy variable covering the period of the introduction of NRT gum and then the nicotine patch but once again found it wanting. Moreover, a great deal of tobacco control activity was occurring around the time that NRT was being introduced, including the very visible efforts of Surgeon General C. Everett Koop. In a time series examining the aggregate measure of per capita cigarette consumption, it was not possible to distinguish subtle effects associated with the availability of smoking cessation therapies.
Conclusions Our findings with regard to all of the individual events, be they tobacco control interventions (e.g., the first surgeon general’s report) or otherwise (e.g., the Great Depression), must be put into context. A regression analysis of the sort presented here cannot be interpreted as yielding definitive causal relationships. Rather, the analysis revealed statistical associations for which we have offered what we believe to be the most likely explanations. Particularly with regard to events that cover a lengthy period of time (e.g., the nonsmokers’ rights movement), we recognize that alternative explanations are possible. The most important take-home message from this study relates not to the precise effects of individual interventions on smoking but rather to the overall impact of tobacco control. Examination of Figure 1 demonstrates that, with a handful of minor exceptions, cigarette smoking rose rapidly throughout the 20th century until the seminal event of the tobacco control era, publication of the 1964 surgeon general’s report. Per capita consumption fell 3.5% that year (5% from the level that would have been expected) and never returned to its 1963 peak. That smoking was destined to continue rising had tobacco control never materialized seems self-evident from the pattern through 1963 and the then escalating rate of smoking among women. The principal qualitative finding of our study thus is no revelation: tobacco control has reduced smoking in this nation substantially. The magnitude of that impact may be surprising, however. Had there been no
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tobacco control—no information development and diffusion, no tobacco control policy, and so forth—and had adult per capita consumption continued to rise as we have posited, almost 5 times as many cigarettes would have been smoked per American adult in 2011 as were actually consumed that year. This remarkable accomplishment notwithstanding, we must remain cognizant that the public health menace of smoking is far from conquered: smoking remains the nation’s, and indeed the world’s, leading cause of preventable illness and avoidable premature death. Short of some currently unanticipated development, the annual smoking-produced death toll in the United States alone will continue to number in the hundreds of thousands for decades to come. Thus, as we celebrate the 50th anniversary of the US tobacco control movement, we must find novel means of rejuvenating the spirit and creativity that have made tobacco control a sparkling jewel in the crown of public health. This means fully using the evidence-based policies documented as effective in our study and in other research and possibly adopting other “out of the box” interventions that are thus far untested.32 j
About the Authors Kenneth E. Warner and Donald W. Sexton are with the Department of Health Management and Policy, School of Public Health, University of Michigan, Ann Arbor. Brenda W. Gillespie is with the Department of Biostatistics, School of Public Health, University of Michigan. David T. Levy is with the Department of Oncology, School of Medicine, Georgetown University, Washington, DC. Frank J. Chaloupka is with the Department of Economics, University of Illinois at Chicago. Correspondence should be sent to Kenneth E. Warner, PhD, Department of Health Management and Policy, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029 (e-mail: kwarner@ umich.edu). Reprints can be ordered at http://www.ajph.org by clicking the “Reprints” link. This article was accepted August 3, 2013.
Contributors K. E. Warner originated the project, supervised the research, and prepared drafts of the article. D. W. Sexton helped conceptualize methods, gathered the data, performed the statistical analysis, helped draft the original article, and assisted with revisions. B. W. Gillespie provided statistical consultation, reviewed the analyses, and reviewed all drafts. D. T. Levy and F. J. Chaloupka assisted with data sources, reviewed the analyses, and reviewed all drafts.
References 1. Smoking and Health: Report of the Advisory Committee to the Surgeon General of the Public Health Service. Washington, DC: US Department of Health, Education, and Welfare; 1964. 2. Agaku I, King B, Dube SR. Current cigarette smoking among adults—United States, 2011. MMWR Morb Mortal Wkly Rep. 2011;61(44):889---894. 3. Reducing the Health Consequences of Smoking: 25 Years of Progress: A Report of the Surgeon General. Washington, DC: US Department of Health and Human Services; 1989. 4. Warner KE. The effects of the anti-smoking campaign on cigarette consumption. Am J Public Health. 1977;67(7):645---650. 5. Warner KE. Cigarette smoking in the 1970s: the impact of the antismoking campaign on consumption. Science. 1981;211(4483):729---731. 6. Warner KE. Effects of the antismoking campaign: an update. Am J Public Health. 1989;79(2):144---151. 7. Alcohol and Tobacco Tax and Trade Bureau. Tobacco statistics. Available at: http://www.ttb.gov/tobacco/ tobacco-stats.shtml. Accessed September 12, 2013. 8. US Census Bureau. Population estimates. Available at: http://www.census.gov/popest/data/index.html. Accessed September 12, 2013. 9. Orzechowski W, Walker RC. Tax burden on tobacco: historical compilation. Available at: http://www. taxadmin.org/fta/tobacco/papers/Tax_Burden_2011. pdf. Accessed September 12, 2013. 10. US Department of Labor. Producer price index commodity data: cigarettes. Available at: http://www.bls. gov/ppi/data.htm. Accessed September 12, 2013. 11. Lebergott S. Annual estimates of unemployment in the United States, 1900---1950. Available at: http:// www.nber.org/chapters/c2644.pdf. Accessed September 12, 2013. 12. Carter SB, Gartner SS, Haines MR, Olmstead AL, Sutch R, Wright G. Historical statistics of the United States: millennial edition online. Available at: http://hsus. cambridge.org. Accessed September 12, 2013.
21. Johnston LD, O’Malley PM, Bachman JG, Schulenberg JE. Decline in teen smoking continues in 2012. Available at: http://www.monitoringthefuture. org/pressreleases/12cigpr.pdf. Accessed September 12, 2013. 22. Norr R. Cancer by the carton. Reader’s Digest. December 1952:7---8. 23. Proctor RN. Golden Holocaust: Origins of the Cigarette Catastrophe and the Case for Abolition. Berkeley, CA: University of California Press; 2011. 24. Chaloupka FJ, Yurekli A, Fong GT. Tobacco taxes as a tobacco control strategy. Tob Control. 2012;21(2): 172---180. 25. Cigarette Tax Evasion: A Second Look. Washington, DC: Advisory Commission on Intergovernmental Relations; 1985. 26. Kluger R. Ashes to Ashes: America’s Hundred-Year Cigarette War, the Public Health, and the Unabashed Triumph of Philip Morris. New York, NY: Vintage Books; 1997. 27. Brandt AM. The Cigarette Century: The Rise, Fall, and Deadly Persistence of the Product That Defined America. New York, NY: Basic Books; 2007. 28. Cummings KM. A century of cigarettes. Available at: http://tobaccotimeline.org. Accessed September 12, 2013. 29. National Association of Attorneys General. Master Settlement Agreement. Available at: http://www.naag. org/backpages/naag/tobacco/msa/msa-pdf. Accessed September 12, 2013. 30. Federal Trade Commission Cigarette Report for 2011. Washington, DC: Federal Trade Commission; 2013. 31. Keeler TE, Hu TW, Ong M, Sung HY. The US national tobacco settlement: the effects of advertising and price changes on cigarette consumption. Appl Econ. 2004;36(15):1623---1629. 32. Smith EA, Warner KE, eds. The tobacco endgame. Tob Control. 2013;22(theme issue):i1---i60.
13. Wynder EL, Graham EA. Tobacco smoking as a possible etiologic factor in bronchiogenic carcinoma: a study of 684 proved cases. JAMA. 1950;143(4): 329---336. 14. Warner KE. Clearing the airwaves: the cigarette ad ban revisited. Policy Anal. 1979;5:435---450. 15. Public Health Cigarette Smoking Act of 1969. Available at: http://tobaccodocuments.org/atc/ 71066088.html. Accessed September 12, 2013. 16. Warner KE. Tobacco policy research: insights and contributions to public health policy. In Warner KE, ed. Tobacco Control Policy. San Francisco, CA: Jossey-Bass; 2006:3---86. 17. The Health Consequences of Smoking: Nicotine Addiction. A Report of the Surgeon General. Washington, DC: US Department of Health and Human Services; 1988. 18. Rogers EM. Diffusion of Innovations. 5th ed. New York, NY: Free Press; 2003.
Human Participant Protection
19. SAS Software, Version 9.3. Cary, NC: SAS Institute; 2013.
No protocol approval was needed because no human participants were involved.
20. Stata Statistical Software: Release 12.1. College Station, TX: StataCorp LP; 2011.
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Impact of Tobacco Control on Adult per Capita Cigarette Consumption in the United States Kenneth E. Warner, PhD, Donald W. Sexton, MHA, MBA, Brenda W. Gillespie, PhD, David T. Levy, PhD, and Frank J. Chaloupka, PhD
January 11, 2014, will mark the 50th anniversary of the release of the first surgeon general’s report on smoking and health,1 widely considered to demarcate the beginning of the tobacco control era in the United States. Tobacco control has consisted of development and dissemination of information on the hazards of smoking, policy implementation, and other interventions in the public, voluntary, and private sectors. These diverse efforts are linked by their dedication to reducing cigarette smoking and, with it, the most grievous toll of disease and death ever wrought by a single product (we use the terms tobacco control, tobacco control era, and tobacco control movement throughout as shorthand to refer to the totality of these efforts). Three measures of cigarette consumption have dominated discussions of the behavioral effects of tobacco control: adult cigarette smoking prevalence, average daily cigarette consumption per smoker, and annual adult per capita cigarette consumption, the latter defined as the total number of cigarettes consumed per year divided by the population older than 17 years. Adult smoking prevalence declined 55% from 1965 to 2011, from 42.4% to 19.0%. The number of cigarettes consumed per smoker per day has been falling steadily, from a peak of nearly 34 cigarettes in 1980 to 18 in 2011.2 Adult per capita consumption, which depends on both prevalence and quantity smoked per smoker, fell 72% between 1963 (the year before the first surgeon general’s report) and 2011, from 4345 cigarettes to 1236. As impressive as these results may be, they do not fully reflect the impact of tobacco control. The assumption implicit in these comparisons is that smoking had peaked immediately before 1964 and, hence, that the contribution of tobacco control has been simply to decrease smoking from those mid-1960s levels. In point of fact, cigarette consumption was rising sharply and quite steadily from
Objectives. We assessed the impact of tobacco control on adult per capita cigarette consumption in the United States from 1964 to 2011. Methods. We used logit regression to model the diffusion of smoking from 1900 to 2011. We also projected hypothetical cigarette consumption after 1963 in the absence of tobacco control. Model predictors included historical events such as wars, specific tobacco control interventions, and other influences. Results. Per capita consumption increased rapidly through 1963, consistent with S-shaped (sigmoid) diffusion. The course reversed beginning in 1964, the year of publication of the first surgeon general’s report on smoking and health. Subsequent tobacco control policy interventions significantly reduced consumption. Had the tobacco control movement never occurred, per capita consumption would have been nearly 5 times higher than it actually was in 2011. Conclusions. Tobacco control has been one of the most successful public health endeavors of the past half century. Still, the remaining burden of smoking in the United States augurs hundreds of thousands of deaths annually for decades to come. Reinvigorating the tobacco control movement will require novel interventions as well as stronger application of existing evidence-based policies. (Am J Public Health. 2014;104:83–89. doi:10.2105/AJPH.2013.301591)
1900 through the early 1960s. It almost certainly would have continued to rise in the absence of the report and subsequent tobacco control initiatives because smoking among women was increasing rapidly at that time, paralleling the diffusion of smoking among men 2 to 3 decades earlier. The onset of the tobacco control movement stalled and eventually reversed the then rapidly growing prevalence of smoking among women.3 Three previous analyses, to our knowledge, have assessed how much higher adult per capita consumption would have been in the absence of tobacco control, reflecting the increases in smoking that would have been anticipated had the movement never materialized.4---6 In the most recent of the 3 studies, Warner found that actual per capita consumption fell by 26% from 1963 to 1987, whereas consumption likely would have been 79% to 89% higher in 1987 had it not been for the salutary effects of tobacco control.6 With no analysis of this phenomenon for a quarter of a century, we believed that it was time to estimate how much tobacco control has
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affected cigarette consumption as the movement concludes its fifth decade. Relative to previous studies, we employed a more sophisticated conceptual model to estimate tobacco control’s effects. The resulting change in methods has no impact on the qualitative conclusions of the earlier studies and indeed only a minor quantitative impact. Had the original methodology been used in our study, however, it would have overestimated the impact of tobacco control considerably.
METHODS Our analysis derives from a model of the diffusion of smoking from 1900 to 2011, one that allowed us to assess the general diffusion pattern over time while evaluating the effects on cigarette consumption of specific events and interventions. Some of the events occurred independent of any interest in smoking but affected smoking nonetheless, including the Great Depression and the nation’s major wars. All but one of the remaining events and
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interventions were clearly intended to decrease smoking, such as publication of the surgeon general’s reports and the introduction of clean indoor air laws. The remaining variable, price, is a well-established determinant of the level of smoking but is neither entirely a tobacco control variable nor a completely independent one, as we discuss later.
We regressed adult per capita consumption of cigarettes against year and the other variables. The regression model variables are presented in Table 1 and discussed in more detail in the Discussion section. The table describes the variables, provides their ranges and mean values, and presents sources and, where appropriate, comments on the variables’
construction. Parameter estimates allowed us to test whether the various events and interventions affected smoking and, if so, to what degree. To project per capita cigarette consumption from 1964 to 2011 in the absence of tobacco control, we assigned values of zero to all of the post-1963 tobacco control variables and held price constant at its 1963 value,
TABLE 1—Variables Included in the Regression Model, Along With Descriptive Information and Data Sources Variable
Year(s) Covered
Dependent variable: adult per capita cigarette consumption
1900–2011
Range or Value 54–4345
Mean
Decaya
Notes
2326
...
Sources: Alcohol and Tobacco Tax and Trade Bureau7 and US Census Bureau8; cigarette consumption is based on tax-paid cigarette sales
Year (calendar year minus 1900)
1900–2011
0–111
...
...
Captures diffusion of smoking over time
1900–2011
1.92–5.61
2.40
...
Source for 1954–2011: Orzechowski and Walker9; for 1926–
Economic indicators Cigarette price, $ (average price/pack of
1953, the tobacco producer price index and consumer price index from the Bureau of Labor Statistics10 were used to
cigarettes in 2011)
create a proxy for average price per pack; for years preceding 1926, average price per pack in 1926 was used Great Depression (unemployment rate minus 5%)
1930–1941
3.90–19.90
12.25
Yes
Source: Lebergott11
Great Depression spline (beginning in 1930)
1930–2011
1.0–83.0
...
...
Captures the modest decrease in the rate of growth of smoking following the Great Depression
Pro-smoking indicators World War I (ratio: total DoD personnel/total US adults) World War II (ratio: total DoD personnel/total US adults)
1916–1918 1941–1945
0.0028–0.045 0.005–0.12
0.013 0.087
Yes Yes
Sources: US Census Bureau8 and Carter et al.12 Sources: US Census Bureau8 and Carter et al.12
Korean War (ratio: total DoD personnel/total US adults)
1950–1953
0.014–0.034
0.016
Yes
Sources: US Census Bureau8 and Carter et al.12
Vietnam War (ratio: total DoD personnel/total US adults)
1965–1971
0.020–0.027
0.024
Yes
Sources: US Census Bureau8 and Carter et al.12
1953–1955
1.0
...
Yes
Represents major cancer and smoking scare following
Tobacco control indicators Cancer scare (dummy variable)
publication of the first definitive science linking smoking to lung cancer13 1964 surgeon general’s report (dummy variable) 1964 surgeon general spline (beginning in 1964)
1964 1964–2011
1.0 1.0–48.0
... ...
Yes ...
First surgeon general’s report1 Permanent adjustment down in the slope of the diffusion curve from its previous upward trajectory; reflects major shift in public knowledge, attitudes, and behaviors in early years of antismoking campaign
Fairness Doctrine (dummy variable)
1967–1970
0.25–1.0
...
Yes
Values: 0.25 in 1967, 0.75 in 1968 , and 1.0 in 1969–1970; period of Fairness Doctrine antismoking ads on television and radio14,15
Nonsmokers’ rights spline (beginning in 1975)
1975–2011
1.0–37.0
...
...
Reflects accelerating decrease in smoking that accompanied the nonsmokers’ rights movement and the era of clean indoor air (or smoke-free) laws beginning with Minnesota’s first model state law in 197516
1988 surgeon general’s report (dummy variable)
1988–1989
0.60–1.0
...
Yes
Values: 0.60 in 1988, 1.0 in 1989; surgeon general’s report on smoking as addictive; released in May, so first-year impact is adjusted to reflect the partial year17
Note. DoD = Department of Defense. a In year after period covered, variable takes on value of 0.75 times the preceding year’s value. Each subsequent year, the value decays by an additional 25%.
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assuming that, in the absence of tobacco control, price would have increased with the general rate of inflation. Comparing the 2011 value of this hypothetical “tobacco control--free” level of smoking with the level actually realized allowed us to estimate the impact of tobacco control on adult per capita cigarette consumption. We modeled the diffusion of smoking over time as a sigmoid or S-shaped curve, a pattern typical of the diffusion of a novel behavior or product adoption, such as cigarette smoking (novel early in the 20th century), as well as of epidemics.18 From the beginning of the 20th century to 1963, the year before the first surgeon general’s report, adult per capita cigarette consumption rose from 54 to 4345, exhibiting growth consistent with an S-shaped curve. The S-shaped curve starts slowly, rises at an exponential rate, reaches an inflection point, and then increases at a diminishing rate as it approaches an asymptotic ceiling. Although we could have performed nonlinear modeling on this S-shaped function directly, we chose to apply the inverse transformation to linearize the function, which allowed ordinary linear models to be used. For subsequent plotting of the fitted model, we transformed back to present the results on the raw scale of cigarette consumption. We used the following logit function to linearize the curve for modeling: PerCapt ð1Þ lnð Þ ¼ 0 þ Xt þ e; 6022 PerCapt where PerCapt is adult per capita consumption in year t, Xt is a vector of the independent variables in year t, is a vector of the regression parameters, and e is an error term. We used a retransformation function to obtain the predicted per capita consumption: ˇ
ˇ
d t ¼ 6022=ð1 þ exp ð0 þXt Þ Þ ð2Þ PerCap
the tobacco control era, male smoking prevalence peaked at about 55%. As noted, smoking among women was increasing at a rate virtually identical to that of men but with a 20- to 30-year lag, its rapid rise interrupted by the beginning of the tobacco control era. In the 1950s and early 1960s, men smoked an average of about 30 cigarettes per day.3 We used SAS19 and Stata20 software in conducting our statistical analyses.
RESULTS Table 2 presents the regression results. Most of the variables were highly significant. Year was included to reflect the diffusion of smoking among the population. Cigarette consumption increased significantly during World Wars I and II and the Korean War (all P < .001), whereas the estimated increase during the Vietnam War was not significant (P = .297). Smoking declined significantly during the Great Depression (P < .001). The rate of growth in smoking slowed somewhat following the depression, as reflected in the significant negative parameter estimate of the Great Depression spline (P < .001). Each of the following tobacco control--related variables decreased smoking: the
TABLE 2—Results of Multivariate Regression Analysis Predicting per Capita Consumption of Cigarettes: United States, 1900–2011 Variable Intercept
b (95% CI)
SE
t
P
–4.83 (–4.94, –4.72)
0.056
–86.28
< .001
Year
0.1326 (0.1297, 0.1355)
0.0015
91.18
< .001
Cigarette price
–0.056 (–0.108, –0.004)
0.026
–2.11
.037
9.81
< .001
World War I
11.8 (9.4, 14.2)
1.2
Great Depression
–0.0208 (–0.0254, –0.0163)
0.0023
–9.06
< .001
Great Depression spline World War II
–0.0714 (–0.0763, –0.0665) 3.21 (2.52, 3.91)
0.0025 0.35
–29.05 9.18
< .001 < .001
Korean War Cancer scare
The function to linearize the sigmoid curve required specification of an asymptote (ceiling) on adult per capita consumption, which we estimated to be 6022 cigarettes per capita. This value was derived by assuming that, in the absence of tobacco control, adult smoking prevalence eventually would have reached 55% and average daily consumption per smoker would have been 30 cigarettes. Prior to
cancer-and-smoking scare in the early 1950s (cancer scare; P < .001), publication of and extensive publicity about the 1964 surgeon general’s report (single-year effect, P = .049; long-term spline effect, P < .001), airing of the Fairness Doctrine antismoking ads on television and radio from mid-1967 through 1970 (P = .001), the adoption and spread of clean indoor air laws beginning in 1975 (nonsmokers’ rights spline, P < .001), and publication of and publicity regarding the 1988 surgeon general’s report on smoking as addiction (P = .008). Price increases also decreased cigarette consumption (P = .037). Figure 1 displays actual per capita consumption between 1900 and 2011 (dotted line), the regression fit to the latter year (solid line), and the hypothetical diffusion of adult per capita cigarette consumption in the absence of any antismoking knowledge and activity (dashed line beginning in 1964). A comparison of the lines of actual and hypothetical consumption provides a visual demonstration of the impact of tobacco control over time. In the absence of tobacco control, per capita consumption would have risen steadily, although at a decelerating rate, reaching a level of 5907 in 2011. In fact, per capita consumption plummeted. Comparing the actual value in
6.7 (3.7, 9.7) –0.234 (–0.335, –0.132)
1.5 0.051
4.49
< .001
–4.57
< .001
1964 Surgeon General’s report
–0.142 (–0.284, –0.001)
0.071
–2.00
.049
1964 Surgeon General spline
–0.0718 (–0.0815, –0.0621)
0.0049
–14.67
< .001
Vietnam War Fairness Doctrine Nonsmokers’ rights spline 1988 Surgeon General’s report
1.05
.297
–0.249 (–0.394, –0.105)
2.6 (–2.3, 7.5)
0.073
2.5
–3.43
.001
–0.0431 (–0.0554, –0.0308) –0.134 (–0.232, –0.036)
0.0062 0.05
–6.95 –2.71
< .001 .008
Note. CI = confidence interval. Values for the overall model were as follows: df = 14; F = 4215.5; P £ .001; R2 = 0.9981.
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FIGURE 1—Actual adult per capita cigarette consumption (dotted line); predicted consumption (solid line); and projected consumption in the absence of tobacco control (dashed line beginning in 1964): United States, 1900–2011.
2011 with the hypothetical value in the absence of tobacco control suggests that, had the tobacco control era never occurred, consumption in 2011 would have been 378% higher than its actual value that year.
DISCUSSION As noted, our analysis differed in methodology from that previously employed by Warner,4---6 who used linear ordinary least squares regression (untransformed) to project future per capita cigarette consumption. Linear projections indicated that, had tobacco control never occurred, per capita consumption would have reached 5075 cigarettes in 1975 and 5449 in 1978. The comparable figures from our model are 5102 and 5238, respectively, 0.5% higher than Warner’s estimate for 1975 and 4% lower for 1978. Warner’s estimate of 6154 in 1987 exceeds our estimate for that year by 11%, and it slightly exceeds the asymptotic ceiling for hypothetical consumption we selected (6022). Thus, although a linear projection was plausible for short-term projections in the earlier studies, it would not work well for more recent years, when the growth in consumption
necessarily would have slowed even in the complete absence of tobacco control, simply reflecting a conventional diffusion process. This is true even if our asymptotic ceiling may be a conservative estimate because some proportion of the population undoubtedly had reacted to the new research on smoking and lung cancer in the 1950s, prior to what we are characterizing as the tobacco control era. As well, we assumed a peak daily cigarette consumption of 30, whereas the actual historical peak was 34. Independent of the specific ceiling chosen, employing a model that represents S-shaped diffusion is both theoretically more appropriate and a better fit to the data through 1963. Regardless of the small differences, however, each of the 4 studies demonstrates that adult per capita consumption is dramatically lower than it would have been in the absence of tobacco control and that it would have been substantially higher than it was in 1963, the year prior to the beginning of the tobacco control era.
Study Limitations Our dependent variable, adult per capita consumption, measures the combined effect of smoking prevalence and daily cigarette consumption by smokers. Still, it suffers from
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a number of limitations. One is the implicit assumption that all cigarette consumption is attributable to adults, clearly not the case. Significant percentages of adolescents smoke (defined as smoking at least 1 cigarette in the past 30 days)21 and changes in their numbers, as well as the amount of cigarettes they smoke, could affect “adult” per capita consumption. Over time, smoking among adolescents has ebbed and flowed quite substantially. However, the total number of cigarettes smoked by nonadults constitutes only a small percentage of all cigarettes consumed, in part because most young smokers consume few cigarettes. And only fluctuations in that small number would matter to the relevance of adult per capita consumption as a marker of national smoking behavior. Our measure is potentially biased by the fact that changes in the age mix of the population could alter cigarette consumption, independent of any fundamental increases or decreases in smoking. So too could changes in the population’s racial/ethnic mix. For example, Hispanics’ smoking prevalence is considerably less than that of Whites, for both genders.2 Thus, the growing proportion of Hispanics in the United States could influence both smoking prevalence and consumption figures. Preliminary results from ongoing research suggest, however, that demographic shifts do not have quantitative impacts on smoking prevalence sufficient to affect our essential analysis or conclusions (J. Tam, Department of Health Management and Policy, School of Public Health, University of Michigan, oral communication, June 2013). The excellent fit of our regression was not surprising, given the inclusion of the year variable and the 3 splines (slope-shifting terms), each of which represents a major shift in the cigarette consumption trajectory. Year reflects the diffusion process through the first half of the 20th century, which would have continued thereafter in the absence of tobacco control. The Great Depression was associated with a slowing of the rate of growth in smoking that was occurring just prior to the depression. It is plausible that slowing of cigarette consumption as a result of widespread poverty over a decade or more might have a dampening effect on the growth of cigarette consumption thereafter.
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Dramatic change in the slope of the per capita consumption curve after 1964—from consistently rising to falling—is associated with the beginning of the tobacco control era (in addition to the immediate effects of the publication of the surgeon general’s report). The postreport era saw a sea change in knowledge of, attitudes toward, and behavior regarding smoking. We interpret the accelerating decrease in smoking dating from the mid-1970s as most plausibly reflecting the introduction and evolution of smoke-free indoor air laws, the principal policy marker of the nonsmokers’ rights movement.
Impact of Individual Tobacco Control Variables Individual tobacco control events and interventions clearly reduced smoking. The initial health-related shock to the escalating diffusion of smoking preceded publication of the 1964 surgeon general’s report. The first compelling scientific evidence associating smoking with lung cancer was published in 1950.13 Much of the smoking public learned about this evidence through popular publications, including a Reader’s Digest article titled “Cancer by the Carton,” published in December 1952.22 Cigarette consumption fell substantially in 1953 and 1954 and was relatively flat in 1955, a trend that we found significant in our regression. Smoking resumed its rapid upward trajectory in 1956 when the cigarette companies’ promotion of then novel filtered cigarettes falsely assured worried smokers that filtration removed the dangerous elements in cigarette smoke.23 Coverage of the iconic 1964 surgeon general’s report, among the top news stories of the year, reduced per capita consumption by about 5% from the level that would have been expected that year in its absence, a finding consistent with estimates in the literature ranging from 3% to 8%.3 Per capita consumption crept upward the next 2 years before beginning an unprecedented 4-year decline widely credited to the broadcast of free (public service announcement) antismoking messages on television and radio. The ads resulted from a Federal Communications Commission decision that cigarette smoking was a controversial public issue and hence that, under the commission’s Fairness
Doctrine, broadcasters had to donate air time to “balance” paid advertising for cigarettes. Although the antismoking messages never received comparable air time, the impact of the novel and even frightening ads was substantial. The messages ended with the banning of cigarette advertising on the airways on January 2, 1971.14,15 The most important development in tobacco control since the Fairness Doctrine likely was the emergence of the nonsmokers’ rights movement, reflected in the adoption of state clean indoor air laws.16 Initially modest in their coverage (e.g., requiring nonsmoking sections of restaurants), if still dramatic for their day, the laws have become increasingly restrictive over time. Today, approximately 30 states require that all workplaces be smoke free, including all restaurants and bars. We see the impact of the nonsmokers’ rights movement in the significant shift downward in the slope of per capita consumption marked by the nonsmokers’ rights spline in our regression. We included 1 surgeon general’s report in addition to the 1964 report in our analysis, believing that it generated the most consequential public attention since 1964: the 1988 report17 confirming that smoking involved addiction. Its parameter estimate indicated a significant downturn in smoking (P = .008). In earlier regressions, other prominent reports did not prove to be statistically significant.
Impact of Taxation Through tax increases, price can be used to decrease smoking and has been on many occasions at all levels of government.24 In the 8 years following the first surgeon general’s report, there was a surge in state excise tax increases presumed to reflect in part state legislators’ reactions to the new antismoking sentiment. This spate of tax increases substantially raised real cigarette prices (nominal prices adjusted for inflation). However, real prices declined for the next decade as states slowed their tax increases in response to concerns about interstate smuggling of cigarettes, generated by large discrepancies in state tax rates.25 Inflation-adjusted prices fluctuated thereafter, with a surge in real price in more recent years.
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Our study is consistent with a finding produced in well over 100 previous studies: price matters in cigarette consumption.24 Tax and associated price increases deserve a significant share of the credit for the recent large declines in cigarette sales, as, for that matter, do the industry’s own wholesale price increases in the face of declining sales. The cigarette price index reflects both influences. Research indicates that for every 10% increase in cigarette price, the demand for cigarettes decreases 3% to 5%. Our methods of estimating price prior to the availability of a consistent measure in 1954 required use of general data on tobacco for the period 1926 to 1953 (price index data) and the arbitrary assumption that price was constant prior to the initial availability of price index data. We tested 4 alternative means of handling the missing data for 1900 to 1925, and all yielded essentially identical results.
Influence of Wars and the Great Depression on Smoking Two factors clearly unrelated to any intention to influence smoking had significant effects: wars and the Great Depression. Indeed, World War I is often credited with playing a role in the early growth of cigarette smoking. Prior to the war, smoking cigarettes was considered effeminate. A large majority of men consumed tobacco products, but chiefly in the form of pipes, cigars, and smokeless tobacco. 26 However, cigarettes were supplied to soldiers as part of their rations during the war. Because the circumstances of warfare did not always afford the time to smoke an entire cigar or to go through the ritual of filling, lighting, and smoking a pipe, cigarettes became the GIs’ preferred method of smoking tobacco. When soldiers came home from the war addicted, cigarette smoking began its rapid escalation. Cigarettes in soldiers’ rations were valued by smoking and nonsmoking soldiers alike, serving for nonsmokers as a medium of exchange for other products and services. The increases in smoking associated with World Wars I and II and the Korean War in our study could reflect a number of factors in addition to the free availability of cigarettes to the military, however. One is simply that war-related stress
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may have induced increases in smoking not only among the soldiers but also among their families at home. We omitted the wartime variables for Desert Storm and Operation Iraqi Freedom, the first 2 wars since the end of inclusion of cigarettes in soldiers’ rations. As well, they involved fewer military personnel. When included in the regression, their parameter estimates were both nonsignificant. Smoking by soldiers in World War I was not the only contemporary factor influencing the national uptake of cigarette smoking, however. Much else was going on in the early part of the 20th century that kick started the cigarette phenomenon. This includes the 1911 breakup of the cigarette company monopoly, which fostered a vigorous competition in the sale of cigarettes; the introduction of the “American blend” of tobaccos, which made inhalation of cigarette smoke far more “palatable”; and the first modern advertising campaign, for Camel cigarettes.23,26,27 We did not include any of these factors in our model. Another factor that affected smoking in the early part of the 20th century was the Great Depression. Especially during its early years, the enormity of the economic downturn was associated with a substantial decrease in smoking. Note, however, that we evaluated consumption of manufactured cigarettes only. Thus, it is possible that some of the observed decline could reflect smokers switching to less expensive roll-your-own (RYO) cigarettes. Lacking RYO data from that period, we cannot assess how much of the downturn reflects true reductions in cigarette smoking and how much it reflects switching to RYOs. It is certainly likely that a substantial portion of the downturn represents genuine reduced consumption by smokers and perhaps some quitting.
Other Potential Variables Not Included in Our Analysis The tobacco control era is characterized by far more events and interventions than we could hope to capture in a times series analysis such as this one.23,26---28 Notably, for example, the 1998 Master Settlement Agreement (MSA) between the attorneys general of the states and the tobacco industry29 had numerous effects on the smoking environment. The MSA settled state lawsuits
against the industry for smoking-related costs in the states’ Medicaid systems, providing states with billions of dollars (although only a tiny proportion has been devoted to tobacco control). It extended the period of required release of millions of previously secret industry documents that have opened the industry’s behind-the-scenes behavior to public scrutiny. It reduced venues for cigarette advertising. Importantly—and reflected in our price index—it resulted in a significant increase in cigarette prices. We did not include the MSA per se in our regression, however, because beyond any impact through the price increase, its inclusion in earlier regressions did not show any statistically significant effect on per capita consumption. This may reflect the difficulty of properly quantifying the MSA’s contributions over time, or it could represent offsetting measures. For example, although the tobacco industry’s marketing venues were reduced by the agreement, the industry poured billions of dollars into alternative marketing opportunities. From 1998 until 2005, the industry doubled its marketing expenditures.30,31 With industry marketing the focus of so much attention in tobacco control, readers may question the absence of any measure of marketing expenditures in our analysis. We included estimates of industry expenditures in earlier versions of the regression. Although expenditures were associated with increases in per capita consumption, the association never reached statistical significance. This may have been attributable in part to the absence of good data on industry expenditures through much of the early period studied. We assumed constant expenditures (in real terms) during those years, but that obviously may have missed substantial changes in expenditure patterns that, had we had the proper data, would have demonstrated an impact of marketing on consumption. Particularly because the first decades of marketing likely played the most important role in the growth of the market, the complete absence of data during that period makes any marketing expenditure variable suspect. We also did not include marketing of a different sort—that oriented toward methods of decreasing smoking: nicotine replacement therapy (NRT) products and other smoking
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cessation pharmaceuticals, introduced in the 1980s and 1990s. We lacked adequate data on either sales or advertising expenditures. We did test the effect of a dummy variable covering the period of the introduction of NRT gum and then the nicotine patch but once again found it wanting. Moreover, a great deal of tobacco control activity was occurring around the time that NRT was being introduced, including the very visible efforts of Surgeon General C. Everett Koop. In a time series examining the aggregate measure of per capita cigarette consumption, it was not possible to distinguish subtle effects associated with the availability of smoking cessation therapies.
Conclusions Our findings with regard to all of the individual events, be they tobacco control interventions (e.g., the first surgeon general’s report) or otherwise (e.g., the Great Depression), must be put into context. A regression analysis of the sort presented here cannot be interpreted as yielding definitive causal relationships. Rather, the analysis revealed statistical associations for which we have offered what we believe to be the most likely explanations. Particularly with regard to events that cover a lengthy period of time (e.g., the nonsmokers’ rights movement), we recognize that alternative explanations are possible. The most important take-home message from this study relates not to the precise effects of individual interventions on smoking but rather to the overall impact of tobacco control. Examination of Figure 1 demonstrates that, with a handful of minor exceptions, cigarette smoking rose rapidly throughout the 20th century until the seminal event of the tobacco control era, publication of the 1964 surgeon general’s report. Per capita consumption fell 3.5% that year (5% from the level that would have been expected) and never returned to its 1963 peak. That smoking was destined to continue rising had tobacco control never materialized seems self-evident from the pattern through 1963 and the then escalating rate of smoking among women. The principal qualitative finding of our study thus is no revelation: tobacco control has reduced smoking in this nation substantially. The magnitude of that impact may be surprising, however. Had there been no
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tobacco control—no information development and diffusion, no tobacco control policy, and so forth—and had adult per capita consumption continued to rise as we have posited, almost 5 times as many cigarettes would have been smoked per American adult in 2011 as were actually consumed that year. This remarkable accomplishment notwithstanding, we must remain cognizant that the public health menace of smoking is far from conquered: smoking remains the nation’s, and indeed the world’s, leading cause of preventable illness and avoidable premature death. Short of some currently unanticipated development, the annual smoking-produced death toll in the United States alone will continue to number in the hundreds of thousands for decades to come. Thus, as we celebrate the 50th anniversary of the US tobacco control movement, we must find novel means of rejuvenating the spirit and creativity that have made tobacco control a sparkling jewel in the crown of public health. This means fully using the evidence-based policies documented as effective in our study and in other research and possibly adopting other “out of the box” interventions that are thus far untested.32 j
About the Authors Kenneth E. Warner and Donald W. Sexton are with the Department of Health Management and Policy, School of Public Health, University of Michigan, Ann Arbor. Brenda W. Gillespie is with the Department of Biostatistics, School of Public Health, University of Michigan. David T. Levy is with the Department of Oncology, School of Medicine, Georgetown University, Washington, DC. Frank J. Chaloupka is with the Department of Economics, University of Illinois at Chicago. Correspondence should be sent to Kenneth E. Warner, PhD, Department of Health Management and Policy, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029 (e-mail: kwarner@ umich.edu). Reprints can be ordered at http://www.ajph.org by clicking the “Reprints” link. This article was accepted August 3, 2013.
Contributors K. E. Warner originated the project, supervised the research, and prepared drafts of the article. D. W. Sexton helped conceptualize methods, gathered the data, performed the statistical analysis, helped draft the original article, and assisted with revisions. B. W. Gillespie provided statistical consultation, reviewed the analyses, and reviewed all drafts. D. T. Levy and F. J. Chaloupka assisted with data sources, reviewed the analyses, and reviewed all drafts.
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13. Wynder EL, Graham EA. Tobacco smoking as a possible etiologic factor in bronchiogenic carcinoma: a study of 684 proved cases. JAMA. 1950;143(4): 329---336. 14. Warner KE. Clearing the airwaves: the cigarette ad ban revisited. Policy Anal. 1979;5:435---450. 15. Public Health Cigarette Smoking Act of 1969. Available at: http://tobaccodocuments.org/atc/ 71066088.html. Accessed September 12, 2013. 16. Warner KE. Tobacco policy research: insights and contributions to public health policy. In Warner KE, ed. Tobacco Control Policy. San Francisco, CA: Jossey-Bass; 2006:3---86. 17. The Health Consequences of Smoking: Nicotine Addiction. A Report of the Surgeon General. Washington, DC: US Department of Health and Human Services; 1988. 18. Rogers EM. Diffusion of Innovations. 5th ed. New York, NY: Free Press; 2003.
Human Participant Protection
19. SAS Software, Version 9.3. Cary, NC: SAS Institute; 2013.
No protocol approval was needed because no human participants were involved.
20. Stata Statistical Software: Release 12.1. College Station, TX: StataCorp LP; 2011.
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