摘要：OBJECTIVES: We developed a simulation model to predict the effects of policies aimed at reducing smoking initiation by youths younger than 18 years. METHODS: The model projected the number of smokers, never smokers, and ex-smokers by age, sex, and racial/ethnic group and the effects of reductions in youth initiation. RESULTS: The model predicted that even if tobacco policies eliminated youth initiation, the number of smokers would not be halved for more than 30 years. If initiation were halved and some of the initiation were delayed rather than eliminated, substantially smaller reductions would result. CONCLUSIONS: Policies that increase cessation rates are needed to reduce the number of current smokers and the more near-term health problems.
