Comparison of the Heavy Smoking Index and of the Fagerstrom Test for Nicotine Dependence in a sample of 749 cigarette smokers.

Nicotine Dependence (FTND) was administered to a sample of 749 adult smokers. The Heavy Smoking Index (HSI) which combines two items of the FTND (the number of cigarettes per day and the time of the first cigarette of the day) was compared to the FTND. A cut-off score equal or greater than 4 on the HSI detected a similar rate of nicotine dependence as a cut-off score equal or greater than 6 on the FTND. HSI had good sensitivity (79.5%) and specificity (96.5%). The concordance between the two instruments was high (Cohen's kappa=0.74). The HSI performed as well on men as on women. The HSI provides a good measure of high nicotine dependence, particularly appropriate for epidemiological surveys.