Introduction: The "conversion rate" from initial experimentation to daily smoking is a potentially important metric of smoking behavior, but estimates of it based on current representative data are lacking.
Methods: The Global Health Data Exchange was searched for representative surveys conducted in English speaking, developed countries after the year 2000 that included questions about ever trying a cigarette and ever smoking daily. The initial search identified 2776 surveys that were further screened for language, location, year, sample size, survey structure, and representativeness. Forty-four surveys that passed the screening process were accessed, and their codebooks were examined to see whether the two questions of interest were included. Eight datasets allowed extraction or estimation of relevant information. Survey quality was assessed with regards to response rates, sampling methods, and data collection procedures. PRISMA guidelines were followed, with explicit rules for approaching derived variables and skip patterns. Proportions were pooled using random effects meta-analysis.
Results: The eight surveys used representative samples of the general adult population. Response rates varied from 45% to 88%. Survey methods were on par with the best practice in this field. Altogether, 216314 respondents were included of whom 60.3% (95% CI = 51.3 to 69.3) ever tried a cigarette. Among them, 68.9% (95% CI = 60.9 to 76.9%) progressed to daily smoking.
Conclusions: Over two-thirds of people who try one cigarette become, at least temporarily, daily smokers. The finding provides strong support for the current efforts to reduce cigarette experimentation among adolescents.
Implications: The transition from trying the first cigarette through occasional to daily smoking usually implies that a recreational activity is turning into a compulsive need that has to be satisfied virtually continuously. The "conversion rate" from initial experimentation to daily smoking is thus a potentially important metric of smoking behavior, but estimates of it based on representative data are lacking. The present meta-analysis addressed this gap. Currently, about two-thirds of nonsmokers experimenting with cigarettes progress to daily smoking. The finding supports strongly the current efforts to reduce cigarette experimentation among adolescents.