Figure 3.
Severity scores for NDSS sub-scales, 2002 vs. 2012. Drive consisted of items related to craving and smoking to relieve symptoms of negative affect. Priority consisted of items related to avoiding situations in which smoking was not allowed. Tolerance consisted of items related to increased number of cigarettes since stated smoking. Continuity consisted of items related to regularity of smoking throughout the day and week. Data source: National Survey on Drug use and Health. ***p < 0.001.