[Evaluation of a "stop smoking" contest in Japan]

In 1988, the Osaka Cancer Prevention and Detection Center developed a self-help smoking cessation program, the "stop smoking" contest, based on the Quit and Win strategy developed in the United States in the early 1980's. It consisted of a two-week preparation period, followed by a four-week complete abstinence period. Participants were asked to try to achieve their goals on their own, using self-help materials, mailed to all applicants. Successful participants--"contest winners"--were awarded prizes by lot. The purpose of the present study is to examine the applicability of the Quit and Win strategy in Japan, through evaluating the effectiveness of the program in general and identifying predictors of successful quitting.

We analyzed the results of three consecutive programs conducted in 1998, 1999, and 2000. The programs defined as "participants" all those who demonstrated that their intentions were sincere by signing on for the contest. Of the participants, those who reported complete abstinence for four weeks were defined as "winners." Finally, of the winners, those who reported successful abstinence during the following six- and twelve-month periods were defined as continuing winners. "Abstinent" status was confirmed through self-reporting letters signed by the subject and two witnesses. We hypothesized that successful quitting would be predicted by demographic and smoking-related variables. Predictors of successful quitting were analyzed statistically using logistic regression.

Of 4,221 applicants, 2,550 (60%) smokers eventually joined the program as "participants." Forty-six percent of the participants reported complete tobacco abstinence during the four-week contest period. Twenty percent of the participants maintained abstinence during the following six months. Fifteen percent maintained abstinence for a full year. Significant predictors of tobacco abstinent for the four-week contest period were as follows; male, more advanced age, being married, lower nicotine dependence, greater readiness for quitting, higher confidence in quitting, and better health. Of these, sex and psychological characteristics for quitting such as readiness and confidence were the only factors significantly correlated with successful abstinence throughout the follow-up periods. Previous longer abstinence experiences and chronic disease did not predict four-week abstinence, though it was significantly correlated with abstinence maintenance during the follow-up periods.

The present "stop smoking" contest, a "Quit and Win" type population-based, self-help smoking cessation program combined with incentives, could be successfully implemented in Japan. The success rate was essentially comparable to those of similar programs previously conducted in other countries, and other types of professional-assisted programs in Japan.