The association between home smoking restrictions and youth smoking behaviour: a review.

OBJECTIVE: To review the available evidence for home smoking restrictions as a useful tool in the prevention of youth smoking and to make recommendations for further research. METHODS: A PubMed search (1 January 1990 to 26 January 2010) identified studies involving youth ≤18 years using extensive criteria. In all, 17 studies relating home smoking restrictions to youth smoking behaviour were identified from titles, abstracts or the full text, as required. Two additional articles were identified by other means. KE, NS and EG reviewed the studies. Differences in interpretation were resolved by discussion, with EG making final decisions. RESULTS: Of the 19 studies, 16 (including the only 2 longitudinal studies) showed at least marginal evidence of an association of home smoking restrictions with reduced adolescent smoking behaviours. Associations were more numerous and stronger in homes without adult smokers, suggesting that even in such homes, lack of a smoke-free home may undermine the parental value of not smoking. Definitions of home smoking rules, adolescent smoking behaviour and treatment of parental smoking varied widely among studies. It is recommend that future research: (1) contrast smoke-free homes for everyone against all others, (2) included an interaction term for parental smoking and having a smoke-free home, or conduct separate analyses for homes with and without parental or other adults smokers and (3) examine early and later stages of the smoking uptake continuum. CONCLUSIONS: While the evidence is suggestive for an effect, further research is required to establish causality using longitudinal designs.

The effect of smoke-free homes on adult smoking behavior: a review.

INTRODUCTION: Smoke-free homes are known to reduce exposure to harmful secondhand smoke. Recent studies suggest that they may also positively affect smoking behavior among smokers themselves. METHODS: We review the literature on the effect of smoke-free homes on adult smoking behavior. The literature search included database (PubMed) and manual searches of related articles and reference lists for English-language studies published from 1 January 1990 to 16 November 2008. RESULTS: We identified 16 cross-sectional and 7 longitudinal studies of the population-level association of smoke-free homes with adult smoking behavior. Additional studies provided population estimates of trends in and correlates of smoke-free homes. Prevalence of smoke-free homes varies but has been increasing over time in the countries studied and was greater among smokers who were younger, of higher income or educational attainment, smoked fewer cigarettes per day, or lived with a nonsmoking adult or child. Both longitudinal and cross-sectional studies showed that smokers who had or who newly implemented a smoke-free home were significantly more likely to make a quit attempt and to be abstinent, after controlling for confounding factors. In longitudinal studies, those who continued to smoke had a modest, but significant, decrease in cigarette consumption at follow-up. DISCUSSION: There is strong and consistent population-level evidence that a smoke-free home is associated with increased smoking cessation and decreased cigarette consumption in adult smokers. As they not only reduce exposure to secondhand smoke but also increase cessation rates, promotion of smoke-free homes should be a key element in tobacco control programs.

Receptivity to tobacco advertising and promotions among young adolescents as a predictor of established smoking in young adulthood.

OBJECTIVES: We investigated whether receptivity to tobacco advertising and promotions during young adolescence predicts young adult smoking 6 years later. METHODS: Two longitudinal cohorts of adolescents drawn from the 1993 and 1996 versions of the California Tobacco Surveys were followed 3 and 6 years later. At baseline, adolescents were aged 12 to 15 years and were not established smokers. The outcome measure was established smoking at final follow-up. Receptivity to cigarette advertising and promotions was included in a multivariate logistic regression analysis along with demographic and other variables. RESULTS: The rate of established smoking at follow-up was significantly greater among members of the 1993 through 1999 cohort (21.0%) than among members of the 1996 through 2002 cohort (15.6%). However, in both cohorts, having a favorite cigarette advertisement and owning or being willing to use a tobacco promotional item showed nearly identical adjusted odds of future adult smoking (1.46 and 1.84, respectively). CONCLUSIONS: Despite the success of tobacco control efforts in reducing youth smoking, tobacco marketing remains a potent influence on whether young adolescents become established smokers in young adulthood (18-21 years of age).

The California Tobacco Control Program's effect on adult smokers: (2) Daily cigarette consumption levels.

OBJECTIVE: To investigate the association of the California Comprehensive Tobacco Control Program with self-reported population trends of cigarette consumption during 1992-2002. SETTING AND PARTICIPANTS: Participants were non-Hispanic white daily smokers (aged 20-64 years, n = 24 317) from the Tobacco Use Supplements to the Current Population Survey (1992-2002). We compared age-specific trends in consumption among daily smokers in three groups of states with differing tobacco control initiatives: California (CA; high cigarette price/comprehensive programme), New York and New Jersey (high cigarette price/no comprehensive programme), and tobacco-growing states (TGS; low cigarette price/no comprehensive programme). RESULTS: There was a general decline in cigarette consumption across all age groups in each category of states between 1992 and 2002, except the oldest age group in the TGS. The largest annual decline in the average number of cigarettes per day was observed among daily smokers in CA who were aged > or = 35 years (-0.41 cigarettes/day/year (95% CI -0.52 to -0.3)). This rate was significantly higher than the -0.22 cigarettes/day/year (95% CI -0.3 to -0.16; p<0.02) observed in same-age daily smokers from New York and New Jersey, and significantly higher than the rate in same-age daily smokers from the TGS (-0.15 cigarettes/day/year (95% CI -0.22 to -0.08; p<0.002)). There were no significant differences across state groups in the decline observed in daily smokers aged 20-34 years. In 2002, only 12% of daily smokers in CA smoked more than a pack per day, which was significantly lower than the 17% in New York and New Jersey, which again was significantly lower than the 25% in the TGS. CONCLUSIONS: The California Tobacco Control Program was associated with significant declines in cigarette consumption among daily smokers aged > or = 35 years of age, which in turn should lead to declines in tobacco-related health effects. The decline in consumption among young adult smokers was a national trend.

The California Tobacco Control Program's effect on adult smokers: (3) Similar effects for African Americans across states.

OBJECTIVE: To compare trends in African-American (AA) and non-Hispanic white (NHW) smoking between states categorised as having three different levels of tobacco control practice in the 1990s. SETTING AND PARTICIPANTS: Analysis of 1992-3 to 2001-2 Tobacco Use Supplements to the Current Population Survey for differences in adult (20-64 years) daily smoking prevalence for AAs and NHWs across states: California (CA; high cigarette price/comprehensive programme), New York (NY) and New Jersey (NJ; high cigarette price/no comprehensive programme), and tobacco growing states (TGS; low cigarette price/no comprehensive programme). RESULTS: From 1992-3 to 2001-2, there were large declines in AA smoking across states (2.7-3.8% decrease/year, adjusted for age, income, education, gender; p<0.05). Adjusted NHW smoking prevalence declined significantly only in CA. AA prevalence declined significantly and did not differ across state groups. In all years, in all state groups, adjusted prevalence was either not significantly different or was lower for AAs than for NHWs. More recent cohorts of AAs appeared to have taken up smoking at lower rates than older cohorts. CONCLUSION: There were uniformly large declines in AA smoking from 1992-3 to 2001-2 across states, independent of type of tobacco control strategy. Further research is needed into factors associated with smoking declines among AAs.

The California Tobacco Control Program's effect on adult smokers: (1) Smoking cessation.

OBJECTIVES: To estimate national population trends in long-term smoking cessation by age group and to compare cessation rates in California (CA) with those of two comparison groups of states. SETTING: Retrospective smoking history of a population sample from the US: from CA, with a comprehensive tobacco-control programme since 1989 with the goal of denormalising tobacco use; from New York and New Jersey (NY & NJ), with similar high cigarette prices but no comprehensive programme; and from the tobacco-growing states (TGS), with low cigarette prices, no tobacco-control programme and social norms relatively supportive of tobacco use. PARTICIPANTS: Respondents to the Current Population Survey-Tobacco Use Supplements (1992-2002; n = 57 918 non-Hispanic white ever-smokers). MAIN OUTCOME MEASURES: The proportion of recent ever-smokers attaining long-term abstinence (quit > or = 1 year) and the successful-quit ratio (the proportion of all ever-smokers abstinent > or = 1 year). RESULTS: Nationally, long-term cessation rates increased by 25% from the 1980s to the 1990s, averaging 3.4% per year in the 1990s. Cessation increased for all age groups, and by > 40% (p<0.001) among smokers aged 20-34 years. For smokers aged < 50 years, higher cigarette prices were associated with higher quitting rates. For smokers aged < 35 years, quitting rates in CA were higher than in either comparison group (p<0.05). Half of the ever-smokers had quit smoking by age 44 years in CA, 47 years in NY & NJ, and by age 54 years in TGS. CONCLUSION: Successful smoking cessation increased by 25% during the 1990s in the US. Comprehensive tobacco-control programmes were associated with greater cessation success than were with high cigarette prices alone, although both effects were limited to younger adults.

Validation of the WHI brief physical activity questionnaire among women diagnosed with breast cancer.

OBJECTIVE: To investigate the psychometric properties of the physical activity (PA) measure of the Women's Health Initiative (WHI). METHODS: Women diagnosed with breast cancer and enrolled in the Women's Healthy Eating and Living Study (average age 55 years) wore an accelerometer for 1 week and completed the 7-day Physical Activity Recall (PAR) and brief WHI measure. RESULTS: Both self-reports correlated 0.73 with the accelerometer and had 100% sensitivity for meeting the current PA guideline, but specificity was significantly higher for the PAR. CONCLUSIONS: The WHI measure had comparable validity, sensitivity, and measurement bias compared to the widely accepted PAR.

Trends in smoking among Hispanic women in California: Relationship to English language use.

BACKGROUND: Research has shown that Hispanic women who speak mostly English have higher smoking rates than those who speak mostly another language. It is unknown how differences in smoking by English language use among adult Hispanic women in California have changed in recent years. METHODS: We compared current daily (100 or more cigarettes in lifetime, now smokes daily) and current nondaily (100 or more cigarettes in lifetime, now smokes some days) smoking prevalence for adult Hispanic women by English language use at home from population-based, random-digit-dialed California Tobacco Surveys in 1996 (n = 1406, 74% response rate [RR]); 1999 (n = 1379, 69% RR), and 2002 (n = 2912, 64% RR). RESULTS: Current smoking prevalence was at least twice as high among those who speak mostly English compared to those who speak mostly another language in every survey year (1996: 14.7% vs 6.1%; 1999: 14.6% vs 6.1%; 2002: 11.7% vs 4.9%) with the ratio staying constant (2.4:1). There was a decline in current nondaily smoking among those who speak mostly English by 2002 (1996 and 1999 prevalence: approximately 6%, 2002: approximately 4%), but no declines in current daily smoking for either language-use group. CONCLUSIONS: There has been no reduction in the English-language-use gap in smoking among Hispanic women in California. There has been a significant decline in current nondaily smoking prevalence among women who speak mostly English, but no significant reduction in current daily smoking for either language-use group. It appears that not much progress has been made in California in reducing daily smoking prevalence among Hispanic women at the population level. Smoking prevention and cessation efforts among Hispanic women remain a priority.

Cigarette promotional offers: who takes advantage?

BACKGROUND: Promotional offers on cigarettes (e.g., dollar-off, multipack discounts) composed the largest share of tobacco industry marketing expenditures, totaling $8.9 billion, or 72% of the total budget in 2002. Internal industry documents indicate that young adults, potential quitters, and other price-sensitive groups are the targets of these marketing tactics. How effective they are in actually reaching these groups in the general population of smokers has not yet been investigated. METHODS: Data were from 4618 current smokers responding to the large, random-digit-dialed population-based 2002 California Tobacco Survey. The characteristics were identified of smokers who reported that they used these offers "every time I see one." RESULTS: Thirty-five percent of smokers used promotional offers every time they saw one. Multivariate analyses identified young adults, women, African Americans, those with higher daily cigarette consumption, and those worried about cigarette costs as more likely to use promotional offers at every opportunity. Smokers most committed to quitting were no more likely to use promotional offers than those with no intention to quit. Cigarette brand was highly correlated with age and race/ethnicity, and therefore was not included in the multivariate analysis. Those who smoked menthol cigarettes and Camels, more often young adults and African Americans, were much more likely than those of other brands to use promotional offers. CONCLUSIONS: With the exception of smokers intending to quit, cigarette promotional offers are effectively reaching most industry-targeted groups. Importantly, young adults, who have the greatest long-term customer potential, are responding.

Comparative validation of the IPAQ and the 7-Day PAR among women diagnosed with breast cancer.

BACKGROUND: The criterion-related validity and measurement bias of the long form of the International Physical Activity Questionnaire (IPAQ) was compared to the 7-Day Physical Activity Recall (PAR). METHODS: Participants were women who have been diagnosed with breast cancer and enrolled in the ongoing Women's Healthy Eating and Living Study. Women (N = 159, average age 57 years) wore an accelerometer for one week and then completed the IPAQ or the PAR. RESULTS: The validity correlation of the PAR was significantly higher (p < 0.001) than the IPAQ (0.73 vs. 0.33, respectively). The PAR and IPAQ overestimated total physical activity by 13% vs. 247%, respectively. The PAR had better sensitivity (p = 0.14) and specificity (p < .01) than the IPAQ (100% vs. 71% and 84% vs. 59%, respectively) in predicting attainment of the ACSM physical activity guideline. CONCLUSION: The PAR was superior to the IPAQ in terms of validity, measurement bias, and screening statistics.

What contributed to the major decline in per capita cigarette consumption during California's comprehensive tobacco control programme?

OBJECTIVES: California experienced a notable decline in per capita cigarette consumption during its comprehensive tobacco control programme. This study examines what proportion of the decline occurred from: (1) fewer ever smokers in the population, (2) more ever smokers quitting, and (3) current smokers smoking less. DESIGN, SUBJECTS: Per capita cigarette consumption computed from cigarette sales and from adult respondents to the large, cross-sectional, population-based California Tobacco Surveys of 1990 (n = 24,296), 1996 (n = 18,616) and 2002 (n = 20,525) were examined for similar trends. MAIN OUTCOME MEASURE: Changes (period 1: 1990-1996; period 2: 1996-2002) in per capita cigarette consumption from self-reported survey data were partitioned for the entire population and for demographic subgroups into the three components mentioned above. RESULTS: In periods 1 and 2, most of the decline in per capita cigarette consumption for the population as a whole was from current smokers smoking less followed by a reduction in ever smokers. The decline from smokers smoking less was particularly evident among young adults (18-29 years) in period 1. While the portion of the decline due to quitting in the entire population in period 1 was negligible, in period 2 it accounted for 22% of the total per capita decline. The decline from quitting in period 2 was mostly observed among women. CONCLUSIONS: Rather than near-term benefits from smokers quitting, population health benefits from reduced per capita cigarette consumption will likely occur over the longer term from fewer people becoming ever smokers, and more less-addicted smokers eventually quitting successfully.

The potential impact of a low-nitrosamine smokeless tobacco product on cigarette smoking in the United States: estimates of a panel of experts.

OBJECTIVE: To predict the impact on tobacco use in the US of a "harm reduction" policy that requires that the smokeless tobacco product meet low nitrosamine standards, but could be marketed with a warning label consistent with the evidence of relative health risks. METHODS: Low nitrosamine smokeless tobacco (LN-SLT) and cigarette use are predicted by a panel of experts using a modified Delphi approach. We specify a thought experiment to isolate the changes that would occur after the new LN-SLT policy was implemented. RESULTS: The panel predicted that the new policy would accelerate a decrease in smoking prevalence from 1.3 to 3.1 percentage points over 5 years compared to the current SLT product policy, with greater effects on males than females. Introduction of the new product was also predicted to result in modest additional use of SLT overall, with the greatest increases among males who initiated tobacco use under the new policy. CONCLUSION: An overall consensus was reached that the introduction of a new LN-SLT product under strict regulations would increase SLT use, but reduce overall smoking prevalence. This reduction would likely yield substantial health benefits, but uncertainties surround the role of marketing and other tobacco control policies.

How have smoking risk factors changed with recent declines in California adolescent smoking?

AIM: To compare predictors of smoking initiation in two longitudinal studies in California conducted during periods when adolescent smoking prevalence was increasing (1993-96) and decreasing (1996-99). DESIGN, SETTING AND PARTICIPANTS: Cohorts of 12-15-year-old never smokers were identified from the cross-sectional 1993 and 1996 California Tobacco Surveys (large population-based telephone surveys) and followed-up 3 years later (1993-96, n = 1764; 1996-99, n = 2119). MEASURES: We compared cohort transition rates to any smoking by follow-up in risk groups defined by known predictors of smoking initiation at baseline. Besides examining predictors individually, risk groups were defined using a multivariate analysis. FINDINGS: Overall, transition to any smoking by follow-up occurred in 38.3 +/- 4.0% (% +/- 95% confidence interval) of never smokers in the 1993-96 cohort and 31.1 +/- 2.6% in the 1996-99 cohort. For most predictors, the transition rate for adolescents with the characteristic was the same or only slightly lower in the 1996-99 cohort compared to the 1993-96 cohort, but the transition rate in those without the characteristic was generally much lower, thus increasing the power of the predictor. The multivariate analysis confirmed that compared to the 1993-96 cohort, transition occurred much less often in the 1996-99 cohort for adolescents at low rather than at medium or high risk of future smoking. CONCLUSIONS: The turnaround in California adolescent smoking in the mid-1990s, when smoking began to decline, appears to come primarily from adolescents already at low risk of future smoking (as defined by a variety of predictors), who transitioned to smoking at much lower rates than previously.

Facilitating adolescent smoking: who provides the cigarettes?

PURPOSE: Most adolescent smokers obtain cigarettes through social sources. We examine the extent to which cigarettes are provided by facilitators of legal age to purchase cigarettes. DESIGN: Analyses of data from the 1999 California Tobacco Survey, a large population-based, random-digit-dialed telephone survey, are reported. SETTING: California. SUBJECTS: Data were from a subset of 1239 adolescent (12-17 years) respondents who reported ever having smoked a cigarette. The response rate for all adolescents selected for interview was 75.5%. MEASURES: We describe cigarette providers to adolescents in social (cigarettes given to the adolescent) and economic (someone else buys cigarettes for the adolescent) transactions by the reported facilitator's age. RESULTS: Of the 82.2% +/- 2.6% of adolescents who had ever smoked who usually obtained cigarettes from others, 21.6% +/- 2.5% used economic transactions; most (60.6% +/- 3.4%) were given cigarettes. The majority (73.3% +/- 3.6%) of those relying on social sources were given cigarettes by someone < 18 years of age; very few were given cigarettes by someone 21+ years old. Most (90.4% +/- 2.0%) usually given cigarettes reported friends as facilitators. Of those who relied on economic transactions, 56.1% +/- 6.6% reported facilitators who were 18- to 20-year-olds, another 24.7% +/- 6.3% had suppliers > or = 21 years of age. Altogether, 80.8% +/- 5.8% of facilitators in economic transactions were > or = 18 years of age. CONCLUSIONS: Until peer approval of smoking and sharing cigarettes and adult facilitation of adolescent smoking is reduced, it will be difficult to significantly reduce adolescents' access to cigarettes.

Diabetes management in San Diego's Chamorro community.

PURPOSE: The purpose of this study was to assess the diabetes risk status, incidence, and morbidity within San Diego's Chamorro community as a foundation to help community leaders and health care providers create culturally customized health promotion interventions. METHODS: The Behavioral Risk Factor Surveillance Survey was used to query a randomly selected, convenience sample of San Diego Chamorros (N = 228) drawn from the Chamorro Directory International. Based on individual survey responses, participants were mailed personalized health-promoting information. Subsequently, they received information that addressed the most commonly observed overall threats to the Chamorro community's health. RESULTS: A higher than average prevalence of diabetes and gestational diabetes was reported by study participants along with a high prevalence of the risk factors associated with the premature onset of diabetes and its consequences. CONCLUSION: Collaborative partnerships between health professionals and community leaders can help identify opportunities and strategies for improving the health of the nation's population subgroups. San Diego's Chamorro community leaders now have a clearer understanding of the prevalence of diabetes risk factors within their community and can begin working with public health educators to create culturally aligned diabetes prevention and management programs. Given the willingness of Chamorro leaders to get involved in the development of a diabetes awareness campaign and the community's closely knit social network, it should be possible to promote (1) community participation in the intervention program, (2) an increase in the community's adherence to recommended behavioral changes, and (3) identification of additional program modifications that will further enhance the program's cultural relevance.

The role of curiosity in smoking initiation.

CONTEXT: Although advertising theories have long viewed curiosity as an intermediate goal to encouraging consumption of a product among previous nonusers, this variable is rarely discussed in psychological theories and its role in smoking uptake has not been addressed adequately. DESIGN AND SETTING: Using a longitudinal design, in 1999, we reinterviewed 12- to 15-year-old adolescent never smokers (N=2119; 970 committed never smokers, 1199 susceptible never smokers) 3 years after they responded to a population survey on tobacco use in California. RESULTS: Logistic regression showed curiosity and susceptibility to smoke were independently associated with increased future smoking in all never smokers. Committed never smokers reporting curiosity were more likely to become susceptible by follow-up than those not curious. A multivariate analysis of committed never smokers from the cross-sectional survey identified best friends who smoke and receptivity to tobacco advertising and promotions as associated with curiosity. CONCLUSIONS: Curiosity may be a critical precursor to smoking. Future research on smoking initiation should examine curiosity and investigate factors influencing it.

Why does adult African-American smoking prevalence in California remain higher than for non-Hispanic whites?

OBJECTIVES: To explain why, contrary to national trends, adult California African-American (AA) smoking prevalence remains higher than for non-Hispanic Whites (W) and to explore how future rates might change. METHODS: Data from the random-digit-dialed California Tobacco Surveys from 1990 to 2002 (N=16,000-21,000) allowed for the examination of differences in current smoking prevalence, ever smoking (uptake), and successful smoking cessation over time by race/ethnicity and age group. RESULTS: African-American (AA) adolescent (12-17 years) smoking prevalence was lower than Ws through 1996, but similar thereafter because of marked declines for Ws. After 1990, AA young adult (18-29 years) smoking prevalence was consistently 25% lower than Ws', and no evidence of delayed AA smoking initiation was seen. However, among older age groups (30-44 years and 45+ years), AA smoking prevalence was much higher, yielding higher overall adult (18+ years) prevalence. While ever smoking (uptake) was generally lower among AAs, successful cessation (5+ years) was much lower among AA adults, especially older age groups. CONCLUSIONS: Continued higher adult California AA smoking prevalence results from less successful quitting in older age groups. Increased successful cessation is critical for reducing near-term prevalence. Long-term forecasting is difficult because both AA and W adolescents now smoke at comparably low rates.

African-American women's perceptions of their most serious health problems.

African Americans experience a disproportionate burden of illness. According to the Centers for Disease Control and Prevention (CDC), heart disease, cancer, cerebrovascular disease and diabetes are the most common causes of mortality among African Americans. Data were gathered from 1,055 African-American women to gain their perspectives of the most serious health problems affecting African-American women and their related knowledge, attitudes and health promoting behaviors. Women listed CDC's top four causes of mortality as their top four most serious health threats. Cancer was reported as a serious health threat by 81% of the participants, whereas heart disease, the most common cause of mortality and a disease amenable to prevention and early intervention, was mentioned by only 31% of the women. Diabetes was reported by 59% of the women and cerebrovascular disease by 52%. As the Health Belief and other theoretical models would predict, awareness of the seriousness of these four disease groups among African-American women was associated with a greater likelihood of adherence for several of the recommended behaviors. Many opportunities exist for raising women's awareness of these four diseases and linking women's growing health awareness with those health promoting behaviors known to reduce morbidity and mortality.

The relative risks of a low-nitrosamine smokeless tobacco product compared with smoking cigarettes: estimates of a panel of experts.

A nine-membered panel of experts was asked to determine expert opinions of mortality risks associated with use of low-nitrosamine smokeless tobacco (LN-SLT) marketed for oral use. A modified Delphi approach was employed. For total mortality, the estimated median relative risks for individual users of LN-SLT were 9% and 5% of the risk associated with smoking for those ages 35 to 49 and > or =50 years, respectively. Median mortality risks relative to smoking were estimated to be 2% to 3% for lung cancer, 10% for heart disease, and 15% to 30% for oral cancer. Although individual estimates often varied between 0% and 50%, most panel members were confident or very confident of their estimates by the last round of consultation. In comparison with smoking, experts perceive at least a 90% reduction in the relative risk of LN-SLT use. The risks of using LN-SLT products therefore should not be portrayed as comparable with those of smoking cigarettes as has been the practice of some governmental and public health authorities in the past. Importantly, the overall public health impact of LN-SLT will reflect use patterns, its marketing, and governmental regulation of tobacco products.

Demographic differences in patterns in the incidence of smoking cessation: United States 1950-1990.

PURPOSE: Current measures of successful quitting are insensitive to changes induced by tobacco control activities. We evaluated whether changes in the incidence of successful quitting, a new measure of cessation, can inform policy makers how population subgroups responded. METHODS: Smokers from National Health Interview Surveys (NHIS) (1965 through 1992, n = 140,199) were used to determine the number of current smokers eligible to quit at the beginning of each year from 1950 through 1990. Incidence of quitting, computed for different demographic subgroups, was the ratio of those newly successfully quit each year to those eligible to quit. RESULTS: Overall, incidence increased over fivefold, from < 1% in 1950 to a still low 5% in 1990. When the health risks of smoking were first disseminated, middle-aged men had the highest quitting incidence. Gender differences in younger smokers occurred following the beginning of the public health campaign of the mid 1960s, as the dangers of smoking to the fetus were documented. Younger adult smokers appeared to increase quitting markedly in the 1970s, around the beginning of the nonsmokers' rights movement. Quitting patterns in middle-aged African Americans were similar to whites, although at much reduced levels. Younger African Americans had low quitting incidence until 1989. Incidence differed by educational attainment; regardless of age, during the 1970s and 1980s, those with some college increased their quitting incidence markedly. CONCLUSION: Incidence of quitting is a sensitive indicator of relatively short-term changes in successful quitting in population subgroups and should facilitate evaluation efforts.