摘要：We compared observed smoking prevalence data for 1995–2002 with predictions derived from a previously published population dynamics model to determine whether the recent trend in smoking prevalence is consistent with the downward pattern we predicted. The observed data fit our projections closely (R 2 = .89). Consistent with the logic underlying the model, we conclude that adult smoking prevalence will continue to fall for the foreseeable future, although at a rate approximately half that of the decline experienced during the 1970s and 1980s. From 1970 to 1990, adult cigarette smoking prevalence fell steadily, from 37.4% in 1970 to 25.5% in 1990. The 1990s presented a very different picture, however. By 1994, successive annual surveys showed that adult smoking prevalence had remained essentially unchanged for 5 years. Some observers concluded that, having gotten rid of the least addicted smokers, the United States was left with a group of “hardcore” smokers who could not quit. Others blamed inadequacies in the deployment of tobacco control resources, some calling for more emphasis on prevention, others blaming inadequate attention to cessation. 1 In 1998, we published a model that described the adult smoking prevalence process, using data from the National Health Interview Survey (NHIS). 2 We concluded that smoking prevalence had not, in fact, stalled. Rather, it followed the downward pattern of the previous 2 decades. Furthermore, it would necessarily continue to fall in the future, albeit gradually. These conclusions were derived from the fact that the overall annual smoking cessation rate exceeded the initiation rate, a condition likely to continue into the future. Also, the apparent stalling of smoking prevalence was likely to be the result of a measurement problem. Because of the continuous flattening of smoking prevalence and the increase of smoking survey frequency during the 1990s, year-to-year changes in prevalence were not large enough to show as statistically significant. In addition, as noted below, in 1992 the NHIS changed the definition of current smoker in a subtle manner that likely increased the prevalence rate slightly. 3 Five years have passed since we published our model, and recent survey results indicate that prevalence is indeed falling. As our analysis was based on data up to 1994, we are now able to compare the observed prevalence data from 1995 to 2002 with our published predictions to examine whether the recent trend is consistent with the downward pattern we predicted.
