Comparing the predictive validity of five cigarette dependence questionnaires.

BACKGROUND To determine whether the long and short versions of the Cigarette Dependence Scale (CDS), the Fagerström Test for Nicotine Dependence (FTND), the Heaviness of Smoking Index (HSI) and the Nicotine Dependence Syndrome Scale (NDSS) predicted smoking abstinence. METHOD We collected data via Internet in 2004-2007 in 2343 current smokers. Follow-up surveys were conducted after 8 days (N=456) and 31 days (N=486). We assessed the ability of dependence ratings to predict smoking abstinence, controlling for confidence and intention to quit smoking. RESULTS All dependence scales were significant predictors of smoking abstinence at the 8-day follow-up, with the CDS being the best predictor (OR: 3.98 per SD unit, 15% of variance explained). Results were similar but stronger among respondents intending to quit (OR: 6.68, 26% of variance explained). At the 31-day follow-up, only the FTND, HSI and NDSS Continuity subscale were still significant, albeit weak, predictors of abstinence (OR: 1.56, 2% of variance explained). CONCLUSION Among the scales under scrutiny, the CDS had the best predictive validity after 8 days. None of the scales explained more than 2% of the variance in abstinence after 31 days.