Psychometric properties of the Nicotine Dependence Syndrome Scale (NDSS) in a sample of smokers treated for their alcohol dependence

The assessment of nicotine dependence with brief instruments is of great relevance for the better detection of this disorder. Here we present the results with the Nicotine Dependence Syndrome Scale (NDSS) by Shiffman, Waters and Hickcox (2004) in a sample of 183 patients treated at an Alcohol Dependence Unit who were also cigarette smokers. The results indicate that the general factor which evaluates nicotine dependence (NDSS-T) has good reliability (Cronbach's alpha = 0.80). Factor analysis identifies four of the five factors proposed in the original version, those of drive, priority, continuity and stereotypy. Reliability of the scales derived ranges from very good (0.80) to moderate (0.63). The NDSS-T correlates significantly with the Fagerstrom Tolerance Questionnaire (FTQ), with the DSM-IV criteria for nicotine dependence assessed through the SCID, and with the number of cigarettes smoked per day. The ROC curves indicate an NDSS-T score of 0.80 under the curve (0.70 for the FTND), showing that it adequately predicts nicotine dependence. This study confirms the utility of this new instrument for assessing nicotine dependence in smokers who also abuse or depend upon alcohol.