Table 2.

Hierarchical Cox Proportional Hazards Regression Model Predicting Risk of Initiating Smoking During the 50-min Delay Period (N = 94)

Variable	Hazard ratio	95% CI	p value
Received alcohol vs. placebo	1.28	0.73–2.27	.39
Told alcohol vs. placebo	1.27	0.73–2.20	.40
Female	0.82	0.45–1.50	.52
Female × told alcohol	4.34	1.36–13.71	.01
FTND	1.27	1.09–1.48	.002
Importance of payment (motivation)	0.82	0.71–0.95	.008
Minnesota Nicotine Withdrawal Scale	1.03	0.97–1.10	.28
Breath holding duration (s)	0.98	0.96–0.99	.03

Note. FTND = Fagerström Test for Nicotine Dependence. In this analysis, time to choosing to smoke was divided into 10 discrete 5-min segments representing the possible time periods in which participants could choose to smoke. Female gender and experimental conditions were centered. Importance of maximizing payments on study tasks (motivation) ranged from 0 to 10.