Table 2.

Statistical summary for nicotine pain intensity estimates

Nicotine pain sensation	Time effect			Menthol stimulation effect			Interaction time by stimulation
	P value (F value)			P value (F value)			P value (F value)
	All	Pre	During	All	Pre	During	All	Pre	During
Stinging (LN)	<0.0001 (3.91)	<0.0001 (3.54)	0.09 (1.56)	0.75 (0.41)	0.70 (0.47)	0.99 (0.04)	0.99 (0.64)	0.96 (0.66)	0.95 (0.67)
Stinging (HN)	<0.0001 (3.41)	<0.0001 (3.13)	0.67 (0.41)	0.85 (0.26)	0.75 (0.40)	0.92 (0.41)	0.38 (1.04)	0.23 (1.16)	0.46 (0.41)
Burning (LN)	<0.0001 (3.01)	<0.0001 (3.33)	0.36 (1.09)	0.95 (0.11)	0.88 (0.22)	0.99 (0.00)	0.82 (0.86)	0.52 (0.97)	0.87 (0.76)
Burning (HN)	<0.0001 (3.35)	<0.0001 (3.99)	0.65 (0.81)	0.21 (1.56)	0.50 (0.80)	0.68 (0.50)	0.95 (0.76)	0.49 (0.99)	0.99 (0.46)

P values were derived from a linear mixed model for repeated measures; statistical significance was evaluated at P < 0.05. LN, low nicotine; HN, high nicotine

All = whole experimental session (stimulus: 0–30), pre = first half of experiment (stimulus: 1–15) and during = second half of experiment (i.e., during menthol application; stimulus: 16–30)