We investigated whether smoking cessation increased in California after a cigarette manufacturer's retail price increase and an increase in the state cigarette excise tax. The sample for this study was drawn from the 1996 and 1999 California Tobacco Surveys. The rate of unsuccessful and successful quit attempts and the rate of abstinence were calculated for each month of the 14-month period preceding each survey administration. We combined the monthly rates for both surveys and used multiple regression modeling to test whether the proportion of smokers reporting a quit attempt and the proportion of smokers reporting abstinence increased during the period following the price increases. We included several covariates in our models to control for factors other than the price increases that could account for any increases observed in quit attempts and abstinence. Because smokers recall quits occurring closer to the date of the survey better than quits occurring further back in time, we included a term in the models representing the number of months elapsed between the survey administration and the reported quit. We also included terms in the models representing the months before and after the over-the-counter (OTC) availability of the nicotine patch and nicotine gum in 1996 to control for the increase in smoking cessation observed following the availability of OTC nicotine replacement therapy (NRT). Lastly, in order to control for increased quits made in January as a result of New Year's resolutions, we included a term in our models for quit attempts and successful quits (abstinence) made during this month. Results of the regression analyses indicated a significantly greater proportion of smokers reported quit attempts (p < 0.05) in the months immediately following the cigarette price increases (after November 1998); however, a significant increase in abstinence was only observed from December 1998 through March 1999 (p < 0.05) relative to abstinence occurring before the price increases.

The Food and Drug Administration approved over-thecounter (OTC) sale of nicotine gum and nicotine patches in 1996. We used data from the 1996 California Tobacco Survey to compare the rates of nicotine replacement therapy (NRT) use and smoking abstinence in California for each month during a period immediately preceding and immediately following the OTC availability of nicotine gum and patches. For smokers eligible to report a quit attempt, the proportion making a quit attempt using NRT and the proportion remaining abstinent was calculated for each of the 12 months prior to the survey interview. Multiple regression modeling of quit attempts and abstinence included a term for the number of months between the quit attempt and survey interview and dummy variables for the months before and after the OTC availability of NRT. Results showed a significant increase in the fraction of smokers using the patch (P < 0.01) and gum (P < 0.05) immediately following their availability OTC. There was also a significantly higher proportion of smokers reporting abstinence with gum use (P < 0.01) and a significant increase in reported abstinence with patch use (P < 0.01) during the period of time immediately following the availability of these products without a prescription. The results of this study suggest that removing the prescription status of NRT products resulted in an immediate increase in quit attempts and smoking abstinence with the use of nicotine gum or patches.

Objective -To estimate initiation rates among individuals aged 10-24 for the calendar years 1907-81.

Objectives: Models previously developed for predicting lung cancer mortality from cigarette smoking intensity and duration based on aggregated prospective mortality data have employed a study of British doctors and have assumed a uniform age of initiation of smoking. We reexamined these models using the American Cancer Society's Cancer Prevention Study I data that include a range of ages of initiation to assess the importance of an additional term for age. Methods: Model parameters were estimated by maximum likelihood, and model fit was assessed by residual analysis, likelihood ratio tests, and χ2 goodness-of-fit tests. Results: Examination of the residuals of a model proposed by Doll and Peto with the Cancer Prevention Study I data suggested that a better fitting model might be obtained by including an additional term specifying the ages when smoking exposure occurred. An extended model with terms for cigarettes smoked per day, duration of smoking, and attained age was found to fit statistically significantly better than the Doll and Peto model (P &lt; 0.001) and to fit well in an absolute sense (goodness-of-fit; P = 0.34). Finally, a model proposed by Moolgavkar was examined and found not to fit as well as the extended model, although it included similar terms (goodness-of-fit; P = 0.007). Conclusions: The addition of age, or another measure of the timing of the exposure to smoking, improves the prediction of lung cancer mortality with Doll and Peto's multiplicative power model.