Background: Cross-national variance in smoking prevalence is relatively well documented. The aim of this study is to estimate levels of smoking persistence across 21 countries with a hypothesized inverse relationship between country income level and smoking persistence.
Methods: Data from the World Health Organization World Mental Health Survey Initiative were used to estimate cross-national differences in smoking persistence--the proportion of adults who started to smoke and persisted in smoking by the date of the survey.
Results: There is large variation in smoking persistence from 25% (Nigeria) to 85% (China), with a random-effects meta-analytic summary estimate of 55% with considerable cross-national variation. (Cochran's heterogeneity Q statistic = 6845; p < 0.001). Meta-regressions indicated that observed differences are not attributable to differences in country's income level, age distribution of smokers, or how recent the onset of smoking began within each country.
Conclusion: While smoking should remain an important public health issue in any country where smokers are present, this report identifies several countries with higher levels of smoking persistence (namely, China and India).