Table 1.

Sample demographics.

Characteristic	Total (N=385)	Placebo (n=93)	Active medication (n=292)
Age (years), M (SD)	45.95 (11.17)	45.86 (11.38)	45.98 (11.12)
Sex, % male	51.9	49.5	52.7
Cigarettes/day, M (SD)	27.70 (10.30)	27.42 (11.12)	27.78 (10.05)
Plasma cotinine (ng/ml), M (SD)	305.30 (125.97)	293.07 (129.68)	309.26 (124.73)
Number of years smoking, M (SD)	28.67 (11.09)	29.51 (11.86)	28.40 (10.84)
Fagerström Test for Nicotine Dependence score, M (SD)	5.05 (1.56)	4.87 (1.42)	5.12 (1.60)

Note. M, mean; SD, standard deviation. All differences nonsignificant by analysis of variance for continuous variables and chi-square for categorical variables.