Significance of the 100-point scale to evaluate perceived tobacco dependence.

BACKGROUND

Smoking cessation is one of the primary targets for risk reduction of atherosclerotic cardiovascular disease. It also leads to the prevention of workers' illness or disability. Validation of a 100-point scale to evaluate perceived tobacco dependence was conducted using a 10-item questionnaire (the Tobacco Dependence Screener; TDS), a 6-item questionnaire (Fagerstrom Test for Nicotine Dependence; FTND), and determining the salivary levels of cotinine at Japanese workplaces.

METHODS

A total of 1023 male smokers completed the TDS and FTND and scored themselves on the 100-point scale for tobacco dependence (Study 1). Of the subjects participating in Study 1, 282 male smokers from one workplace presented saliva samples, and the salivary nicotine and cotinine levels were determined by high-performance liquid chromatography (Study 2). After conducting principal axis factor analysis, multiple regression analysis was employed to clarify the association between the score on the 100-point scale for perceived tobacco dependence and several factors such as age, the TDS score, the FTND score, and the salivary cotinine level.

RESULTS

The mean age for the subjects was 40.3 years. The mean salivary cotinine level was 235.4 ng/ml, and it increased significantly with increase in the number of cigarettes smoked per day. Cronbach's alpha coefficients for the TDS and FTND were 0.77 and 0.64, respectively. A ROC analysis indicated a cutoff point for the score on the 100-point scale of 61, which yielded a positive result on the TDS ( 5) with 65.7% sensitivity and 70.0% specificity. When FTND 4 was adopted as the gold standard, the sensitivity and specificity became 68.7% and 73.2%, respectively. Three factors were extracted by principal axis factor analysis, explaining 42% of the total variation. Multiple regression analysis revealed that the score on the 100-point scale for evaluating tobacco dependence was positively associated with the TDS and FTND scores, and negatively associated with the age. The adjusted multiple correlation coefficient was 0.262.

CONCLUSIONS

The 100-point scale, which is a simple and easy tool to evaluate tobacco dependence, must be used in combination with other tobacco dependence questionnaires such as TDS and FTND and also the salivary cotinine level as a biological marker of tobacco exposure to conduct multi-dimensional education to promote smoking cessation.