Current FTND scores differed significantly by birth cohort. FTND was highest among those born 1945–1975 (mean=5.1; Table 1), followed by those born <1945 (mean=4.7), and lowest among those born >1975 (mean=4.2). Moreover, birth cohort differed significantly for each FTND item (X2 p<0.05). Response patterns for FTND items varied greatly. For example, 27.1% of those born <1945 reported having their first cigarette within 5 minutes of waking, compared with 38.8% of those born 1945–1975, and 39.3% of those born >1975.
