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.